I've created a package with all necessary document types and other resources but after installing the package on a fresh Umbraco setup and when I try to create a document type from the package it will create it but with default values only and saving always fails with this error message while it's working fine on the main Umbraco setup:

Unexpected character encountered while parsing value: S. Path '', line 0, position 0.

log file:

                             {
            "@t": "2019-04-10T07:32:30.9770713Z",
            "@mt": "Unhandled controller exception occurred for request '{RequestUrl}'",
            "@l": "Error",
            "@x":  "Newtonsoft.Json.JsonReaderException: Unexpected character encountered while parsing value: S. Path '',
                    line 0, position 0.\r\n   at Newtonsoft.Json.JsonTextReader.ParseValue()\r\n  
                    at Newtonsoft.Json.JsonReader.ReadForType(JsonContract contract, Boolean hasConverter)\r\n  
                    at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.Deserialize(JsonReader reader, Type objectType, Boolean checkAdditionalContent)\r\n
                    at Newtonsoft.Json.JsonSerializer.DeserializeInternal(JsonReader reader, Type objectType)\r\n 
                    at Newtonsoft.Json.JsonConvert.DeserializeObject(String value, Type type, JsonSerializerSettings settings)\r\n
                    at Newtonsoft.Json.JsonConvert.DeserializeObject[T](String value, JsonSerializerSettings settings)\r\n 
                    at Umbraco.Web.PropertyEditors.NestedContentPropertyEditor.NestedContentPropertyValueEditor.FromEditor(ContentPropertyData editorValue, Object currentValue)\r\n
                    at Umbraco.Web.Editors.ContentControllerBase.MapPropertyValuesForPersistence[TPersisted,TSaved](TSaved contentItem, ContentPropertyCollectionDto dto, Func`3 getPropertyValue, Action`3 savePropertyValue, String culture)\r\n
                    at Umbraco.Web.Editors.ContentController.MapValuesForPersistence(ContentItemSave contentSave)\r\n   at Umbraco.Web.Editors.ContentController.PostSaveInternal(ContentItemSave contentItem, Func`2 saveMethod)\r\n 
                    at lambda_method(Closure , Object , Object[] )\r\n   at System.Web.Http.Controllers.ReflectedHttpActionDescriptor.ActionExecutor.<>c__DisplayClass6_2.<GetExecutor>b__2(Object instance, Object[] methodParameters)\r\n
                    at System.Web.Http.Controllers.ReflectedHttpActionDescriptor.ExecuteAsync(HttpControllerContext controllerContext, IDictionary`2 arguments, CancellationToken cancellationToken)\r\n--- End of stack trace from previous location where exception was thrown ---\r\n
                    at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()\r\n
                    at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)\r\n
                    at System.Web.Http.Controllers.ApiControllerActionInvoker.<InvokeActionAsyncCore>d__1.MoveNext()\r\n--- End of stack trace from previous location where exception was thrown ---\r\n
                    at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()\r\n
                    at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)\r\n 
                    at System.Web.Http.Filters.ActionFilterAttribute.<CallOnActionExecutedAsync>d__6.MoveNext()\r\n--- End of stack trace from previous location where exception was thrown ---\r\n
                    at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()\r\n 
                    at System.Web.Http.Filters.ActionFilterAttribute.<CallOnActionExecutedAsync>d__6.MoveNext()\r\n--- End of stack trace from previous location where exception was thrown ---\r\n
                    at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()\r\n
                    at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)\r\n
                    at System.Web.Http.Filters.ActionFilterAttribute.<ExecuteActionFilterAsyncCore>d__5.MoveNext()\r\n--- End of stack trace from previous location where exception was thrown ---\r\n
                    at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()\r\n
                    at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)\r\n
                    at System.Web.Http.Filters.ActionFilterAttribute.<CallOnActionExecutedAsync>d__6.MoveNext()\r\n--- End of stack trace from previous location where exception was thrown ---\r\n
                    at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()\r\n
                    at System.Web.Http.Filters.ActionFilterAttribute.<CallOnActionExecutedAsync>d__6.MoveNext()\r\n--- End of stack trace from previous location where exception was thrown ---\r\n
                    at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()\r\n
                    at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)\r\n
                    at System.Web.Http.Filters.ActionFilterAttribute.<ExecuteActionFilterAsyncCore>d__5.MoveNext()\r\n--- End of stack trace from previous location where exception was thrown ---\r\n
                    at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()\r\n
                    at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)\r\n
                    at System.Web.Http.Filters.ActionFilterAttribute.<CallOnActionExecutedAsync>d__6.MoveNext()\r\n--- End of stack trace from previous location where exception was thrown ---\r\n
                    at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()\r\n
                    at System.Web.Http.Filters.ActionFilterAttribute.<CallOnActionExecutedAsync>d__6.MoveNext()\r\n--- End of stack trace from previous location where exception was thrown ---\r\n
                    at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()\r\n
                    at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)\r\n
                    at System.Web.Http.Filters.ActionFilterAttribute.<ExecuteActionFilterAsyncCore>d__5.MoveNext()\r\n--- End of stack trace from previous location where exception was thrown ---\r\n
                    at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()\r\n
                    at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)\r\n
                    at System.Web.Http.Filters.ActionFilterAttribute.<CallOnActionExecutedAsync>d__6.MoveNext()\r\n--- End of stack trace from previous location where exception was thrown ---\r\n
                    at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()\r\n
                     at System.Web.Http.Filters.ActionFilterAttribute.<CallOnActionExecutedAsync>d__6.MoveNext()\r\n--- End of stack trace from previous location where exception was thrown ---\r\n
                     at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()\r\n   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)\r\n
                     at System.Web.Http.Filters.ActionFilterAttribute.<ExecuteActionFilterAsyncCore>d__5.MoveNext()\r\n--- End of stack trace from previous location where exception was thrown ---\r\n
                     at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()\r\n   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)\r\n
                     at System.Web.Http.Filters.ActionFilterAttribute.<CallOnActionExecutedAsync>d__6.MoveNext()\r\n--- End of stack trace from previous location where exception was thrown ---\r\n
                     at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()\r\n
                    at System.Web.Http.Filters.ActionFilterAttribute.<CallOnActionExecutedAsync>d__6.MoveNext()\r\n--- End of stack trace from previous location where exception was thrown ---\r\n
                    at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()\r\n
                    at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)\r\n
                    at System.Web.Http.Filters.ActionFilterAttribute.<ExecuteActionFilterAsyncCore>d__5.MoveNext()\r\n--- End of stack trace from previous location where exception was thrown ---\r\n
                    at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()\r\n
                    at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)\r\n
                    at System.Web.Http.Filters.ActionFilterAttribute.<CallOnActionExecutedAsync>d__6.MoveNext()\r\n--- End of stack trace from previous location where exception was thrown ---\r\n
                    at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()\r\n
                    at System.Web.Http.Filters.ActionFilterAttribute.<CallOnActionExecutedAsync>d__6.MoveNext()\r\n--- End of stack trace from previous location where exception was thrown ---\r\n
                    at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()\r\n
                    at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)\r\n
                    at System.Web.Http.Filters.ActionFilterAttribute.<ExecuteActionFilterAsyncCore>d__5.MoveNext()\r\n--- End of stack trace from previous location where exception was thrown ---\r\n
                    at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()\r\n
                    at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)\r\n
                    at System.Web.Http.Filters.ActionFilterAttribute.<CallOnActionExecutedAsync>d__6.MoveNext()\r\n--- End of stack trace from previous location where exception was thrown ---\r\n
                    at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()\r\n
                    at System.Web.Http.Filters.ActionFilterAttribute.<CallOnActionExecutedAsync>d__6.MoveNext()\r\n--- End of stack trace from previous location where exception was thrown ---\r\n
                    at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()\r\n
                    at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)\r\n
                    at System.Web.Http.Filters.ActionFilterAttribute.<ExecuteActionFilterAsyncCore>d__5.MoveNext()\r\n--- End of stack trace from previous location where exception was thrown ---\r\n
                    at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()\r\n
                    at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)\r\n
                    at System.Web.Http.Filters.ActionFilterAttribute.<CallOnActionExecutedAsync>d__6.MoveNext()\r\n--- End of stack trace from previous location where exception was thrown ---\r\n
                    at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()\r\n
                    at System.Web.Http.Filters.ActionFilterAttribute.<CallOnActionExecutedAsync>d__6.MoveNext()\r\n--- End of stack trace from previous location where exception was thrown ---\r\n
                    at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()\r\n
                    at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)\r\n
                    at System.Web.Http.Filters.ActionFilterAttribute.<ExecuteActionFilterAsyncCore>d__5.MoveNext()\r\n--- End of stack trace from previous location where exception was thrown ---\r\n
                    at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()\r\n
                    at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)\r\n
                    at System.Web.Http.Filters.ActionFilterAttribute.<CallOnActionExecutedAsync>d__6.MoveNext()\r\n--- End of stack trace from previous location where exception was thrown ---\r\n
                    at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()\r\n
                    at System.Web.Http.Filters.ActionFilterAttribute.<CallOnActionExecutedAsync>d__6.MoveNext()\r\n--- End of stack trace from previous location where exception was thrown ---\r\n
                    at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()\r\n
                    at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)\r\n
                    at System.Web.Http.Filters.ActionFilterAttribute.<ExecuteActionFilterAsyncCore>d__5.MoveNext()\r\n--- End of stack trace from previous location where exception was thrown ---\r\n
                    at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()\r\n
                    at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)\r\n
                    at System.Web.Http.Controllers.ActionFilterResult.<ExecuteAsync>d__5.MoveNext()\r\n--- End of stack trace from previous location where exception was thrown ---\r\n
                    at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()\r\n
                    at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)\r\n
                    at System.Web.Http.Filters.AuthorizationFilterAttribute.<ExecuteAuthorizationFilterAsyncCore>d__3.MoveNext()\r\n--- End of stack trace from previous location where exception was thrown ---\r\n
                    at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()\r\n
                    at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)\r\n
                    at System.Web.Http.Filters.AuthorizationFilterAttribute.<ExecuteAuthorizationFilterAsyncCore>d__3.MoveNext()\r\n--- End of stack trace from previous location where exception was thrown ---\r\n
                    at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()\r\n
                    at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)\r\n
                    at System.Web.Http.Filters.AuthorizationFilterAttribute.<ExecuteAuthorizationFilterAsyncCore>d__3.MoveNext()\r\n--- End of stack trace from previous location where exception was thrown ---\r\n
                    at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()\r\n
                    at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)\r\n
                    at System.Web.Http.Filters.AuthorizationFilterAttribute.<ExecuteAuthorizationFilterAsyncCore>d__3.MoveNext()\r\n--- End of stack trace from previous location where exception was thrown ---\r\n
                    at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()\r\n
                    at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)\r\n
                    at System.Web.Http.Controllers.ExceptionFilterResult.<ExecuteAsync>d__6.MoveNext()",
            "RequestUrl": "http://localhost:10613/umbraco/backoffice/UmbracoApi/Content/PostSave",
            "SourceContext": "Umbraco.Web.Editors.ContentController",
            "ProcessId": 28816,
            "ProcessName": "iisexpress",
            "ThreadId": 29,
            "AppDomainId": 10,
            "AppDomainAppId": "LMW3SVC2ROOT",
            "MachineName": "DESKTOP-B4RHN6J",
            "Log4NetLevel": "ERROR",
            "HttpRequestNumber": 3,
            "HttpRequestId": "49a67493-2907-4506-a250-5eba1fc239fd"
        }