Error adding record

Apologies if this is the wrong forum
I have a project using vb.net and MVC with EF6 for a web application to read and write direct to CRM via CData connector

I have created a model class to read CRM Annotations. when trying to add a new record I keep getting the error that it cannot update the CreatedOn field as it read only. I don't want to add or amend that field as CRM candles this when the record is created. I have to have it in my class to be able to display the created date ...

Code for the adding for the record
If ModelState.IsValid Then
Dim AddNote = db.ClientNotes.Create()
AddNote.Id = Guid.NewGuid.ToString
AddNote.ObjectId_Id = Id.ToString
AddNote.Subject = "Account Details Changed"
AddNote.NoteText = "modified the following fields " & Updatedstring
db.ClientNotes.Add(AddNote)
db.SaveChanges()
End If

Class

<Table("Annotation")>
Public Class Notes

<Key>
<Display(Name:="Record ID")>
Public Property Id As String
Public Property ObjectId_Id As String
<Display(Name:="Subject")>
Public Property Subject As String
<Display(Name:="Note")>
Public Property NoteText As String

<Editable(False)>
Public Property CreatedOn As Date

End Class

I have tried with and without the the Editable tag, but keep getting this error

System.Data.Entity.Infrastructure.DbUpdateException
HResult=0x80131501
Message=An error occurred while updating the entries. See the inner exception for details.
Source=EntityFramework
StackTrace:
at System.Data.Entity.Internal.InternalContext.SaveChanges()
at System.Data.Entity.Internal.LazyInternalContext.SaveChanges()
at System.Data.Entity.DbContext.SaveChanges()
at Cashbacs2021_1.Controllers.BankDataCreditController.AddNotes(String Id, String Updatedstring) in C:\Work\2021\Cashbacs2021_1\Cashbacs2021_1\Controllers\BankDataCreditController.vb:line 119
at Cashbacs2021_1.Controllers.BankDataCreditController.Edit(EditCRBankdataModel model) in C:\Work\2021\Cashbacs2021_1\Cashbacs2021_1\Controllers\BankDataCreditController.vb:line 102
at System.Web.Mvc.ActionMethodDispatcher.Execute(ControllerBase controller, Object[] parameters)
at System.Web.Mvc.ReflectedActionDescriptor.Execute(ControllerContext controllerContext, IDictionary`2 parameters)
at System.Web.Mvc.ControllerActionInvoker.InvokeActionMethod(ControllerContext controllerContext, ActionDescriptor actionDescriptor, IDictionary`2 parameters)
at System.Web.Mvc.Async.AsyncControllerActionInvoker.<>c.<BeginInvokeSynchronousActionMethod>b__9_0(IAs yncResult asyncResult, ActionInvocation innerInvokeState)
at System.Web.Mvc.Async.AsyncResultWrapper.WrappedAsyncResult`2.CallEndDelegate(IAsyncResult asyncResult)
at System.Web.Mvc.Async.AsyncResultWrapper.WrappedAsyncResultBase`1.End()
at System.Web.Mvc.Async.AsyncControllerActionInvoker.EndInvokeActionMethod(IAsyncResult asyncResult)
at System.Web.Mvc.Async.AsyncControllerActionInvoker.AsyncInvocationWithFilters.<>c__DisplayClass11_0.< InvokeActionMethodFilterAsynchronouslyRecursive>b__0()
at System.Web.Mvc.Async.AsyncControllerActionInvoker.AsyncInvocationWithFilters.<>c__DisplayClass11_2.< InvokeActionMethodFilterAsynchronouslyRecursive>b__2()

Inner Exception 1:
UpdateException: An error occurred while updating the entries. See the inner exception for details.

Inner Exception 2:
DynamicsCRMException: [500] Could not execute the specified command: Could not update the read-only column CreatedOn.

Inner Exception 3:
hX: Could not update the read-only column CreatedOn.

Inner Exception 4:
hX: Could not update the read-only column CreatedOn.