I'm faceing An Issue when Creating Api For Account Management The Api Works Fine But The Problem Appreas When Back Office Login To Umbraco find Error Attached Below, I TRied To delete all dll in bin folder clean and Rebild But It doesn't work same issue still exists

also here's some logs from log file

{ "@t": "2021-10-04T11:12:18.3923120Z", "@mt": "Unhandled controller exception occurred for request '{RequestUrl}'", "@l": "Error", "@x": "System.ArgumentException: A route named 'ExternalLogin' is already in the route collection. Route names must be unique.\r\nParameter name: name\r\n at System.Web.Routing.RouteCollection.Add(String name, RouteBase item)\r\n at System.Web.Http.WebHost.Routing.HostedHttpRouteCollection.Add(String name, IHttpRoute route)\r\n at System.Web.Http.Routing.AttributeRoutingMapper.AddGenerationHooksForSubRoutes(HttpRouteCollection routeTable, IEnumerable1 entries)\r\n at System.Web.Http.Routing.AttributeRoutingMapper.<>c__DisplayClass1_0.<MapAttributeRoutes>b__0(HttpConfiguration config)\r\n at System.Web.Http.HttpConfiguration.ApplyControllerSettings(HttpControllerSettings settings, HttpConfiguration configuration)\r\n at System.Web.Http.Controllers.HttpControllerDescriptor.InvokeAttributesOnControllerType(HttpControllerDescriptor controllerDescriptor, Type type)\r\n at System.Web.Http.Controllers.HttpControllerDescriptor.InvokeAttributesOnControllerType(HttpControllerDescriptor controllerDescriptor, Type type)\r\n at System.Web.Http.Controllers.HttpControllerDescriptor.InvokeAttributesOnControllerType(HttpControllerDescriptor controllerDescriptor, Type type)\r\n at System.Web.Http.Controllers.HttpControllerDescriptor.InvokeAttributesOnControllerType(HttpControllerDescriptor controllerDescriptor, Type type)\r\n at System.Web.Http.Controllers.HttpControllerDescriptor.InvokeAttributesOnControllerType(HttpControllerDescriptor controllerDescriptor, Type type)\r\n at System.Web.Http.Controllers.HttpControllerDescriptor..ctor(HttpConfiguration configuration, String controllerName, Type controllerType)\r\n at Umbraco.Web.Trees.ApplicationTreeController.<GetApiControllerProxy>d__8.MoveNext() in D:\\a\\1\\s\\src\\Umbraco.Web\\Trees\\ApplicationTreeController.cs:line 262\r\n--- End of stack trace from previous location where exception was thrown ---\r\n at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)\r\n at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)\r\n at Umbraco.Web.Trees.ApplicationTreeController.<GetChildren>d__7.MoveNext() in D:\\a\\1\\s\\src\\Umbraco.Web\\Trees\\ApplicationTreeController.cs:line 229\r\n--- End of stack trace from previous location where exception was thrown ---\r\n at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)\r\n at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)\r\n at Umbraco.Web.Trees.ApplicationTreeController.<GetTreeRootNode>d__5.MoveNext() in D:\\a\\1\\s\\src\\Umbraco.Web\\Trees\\ApplicationTreeController.cs:line 179\r\n--- End of stack trace from previous location where exception was thrown ---\r\n at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)\r\n at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)\r\n at Umbraco.Web.Trees.ApplicationTreeController.<GetApplicationTrees>d__3.MoveNext() in D:\\a\\1\\s\\src\\Umbraco.Web\\Trees\\ApplicationTreeController.cs:line 87\r\n--- End of stack trace from previous location where exception was thrown ---\r\n at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)\r\n at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)\r\n at System.Threading.Tasks.TaskHelpersExtensions.<CastToObject>d__11.MoveNext()\r\n--- End of stack trace from previous location where exception was thrown ---\r\n at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)\r\n at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)\r\n at System.Web.Http.Controllers.ApiControllerActionInvoker.