I need to sort my backend items in alphabetical where published item is at the bottom and the unpublished at top, but Im doing something wrong I don't know the type I have to use, I tried IContent and Document, they get sorted but it seams like they get duplicated also ?, I guess that's because Im making a new item in the database by saving the node again after changing the sortnr.

int sortNr = 0;

// unpublished 
var contentService = ApplicationContext.Current.Services.ContentService;
List<Umbraco.Core.Models.IContent> unpublished = contentService.GetChildren(parentNodeToSortedItems.Id).Where(x => !x.Published).OrderBy(x => x.Name).ToList();

// published
List<Document> publishedItems = new List<Document>();
List<umbraco.interfaces.INode> published = parentNodeToSortedItems.ChildrenAsList.OrderBy(x => x.Name).ToList();

        foreach (var item in published )
        {
            Document document = new Document(item.Id);
            publishedItems.Add(document);
        }

        for (int i = 0; i < unpublished.Count; i++)
        {
            unpublished[i].SortOrder = i;
            contentService.Save(unpublished[i]);
            sortNr++;
        }
        for (int i = 0; i < p.Count; i++)
        {
            p[i].sortOrder = sortNr;

            p[i].SaveAndPublish(new umbraco.BusinessLogic.User(0));
            sortNr++;
        }