Error when run the code a second time without Re-opening the workbook

Hi all,

If I open the workbook and run the below code, it runs fine. However if I run the form and run the code a second time without reopening the workbook, I get method add of object listrows failed. I have added the listbox resource to UserForm_Initialize, any ideas?

 Private Sub CmdAddEng_Click()

Dim Sh As Worksheet
Dim table_List_Object As ListObject
Dim table_object_Row As ListRow

Set Sh = Sheets("Engineers")
Set table_List_Object = Sh.ListObjects(1)
Set table_object_Row = table_List_Object.ListRows.Add

table_object_Row.Range(1, 1).Value = TxtEngName.Text

If ChkContractor.Value = True Then
    
    table_object_Row.Range(1, 2).Value = TxtEngName.Text
    
End If

End Sub