Check file name

I have code in the workbook_Open event that checks the file name has not been change. Before applying XLS Padlock, the code works as expected. How can I apply this code to ensure it checks the file name has not been change?

Thank you kindly.

FNname = Split(ThisWorkbook.Name, “.”)(0)

If FNname <> “My Workbook” Then
MsgBox “Access Denied! Unauthorize name change detected. My Workbook is a copyrighted application.”, vbCritical
tFlg = True

With Application
.DisplayAlerts = False
.Quit
End With: Exit Sub
End If

Instead of exiting the app silently, maybe you can just close the workbook? When the workbook is closed, there is no way for the user to reopen it without closing Excel and starting the EXE file again.