I'm getting an "Application or Object defined error" when I run the
following and it tries to delete an AllowEditRange

Private Sub defineEditableRanges()
   ' defines the areas that can be edited on the protected worksheet.
   Const roomsTitle = "RoomNamesAndNumbers"
   Const deptTitle = "DeptAndPersonnel"
   Dim myRange As Range
   Dim wkSheet As Worksheet
   Set myRange = Columns("A:B")
   Set wkSheet = ActiveSheet
   ' first clear out any old ones -----------------------------> I need
something like this or else I'll get an error when I try to add the same
range again
   For Each er In wkSheet.Protection.AllowEditRanges
       If er.Title = roomsTitle Then
           er.Delete ------------------------------------------> Where I
get the error
       ElseIf er.Title = deptTitle Then
           er.Delete
       End If
   Next
   wkSheet.Protection.AllowEditRanges.Add Title:=roomsTitle, Range:=myRange
   Set myRange = Rows("4:5")
   wkSheet.Protection.AllowEditRanges.Add Title:=deptTitle, Range:=myRange
End Sub

TIA for any insights