Lock cells in Excel

After setting up VB to lock cells in Excel I now need to lock additional cells. I currently have the following script (kindly given by rizvisa1) which is working well.
Private Sub Worksheet_Change(ByVal Target As Range)

If Not (Application.Intersect(Target, Range("M7:M1005")) _
Is Nothing) Then
With Target
If Not .HasFormula Then
Application.EnableEvents = False
.Value = UCase(.Value)
Application.EnableEvents = True
End If
End With
End If
If Not (Application.Intersect(Target, Range("R7:R1005")) _
Is Nothing) Then
With Target
If Not .HasFormula Then
Application.EnableEvents = False
.Value = UCase(.Value)
Application.EnableEvents = True
End If
End With
End If

Dim rowId As Long
If (Intersect(Target, Range(Cells(1, "M"), Cells(1005, "M"))) Is Nothing) Then
Exit Sub
End If
ActiveSheet.Unprotect ("")
For Each Row In Target.Rows
rowId = Row.Row
Range(Cells(rowId, "A"), Cells(rowId, "M")).Locked = (Cells(rowId, "M") = "Y")
Next
ActiveSheet.Protect ("")

End Sub


First part just makes sure columns "M" and "R" are in uppercase. the second part will lock cells in columns "A" to "M" for the row that has a Y in column "M", this is working fine.


What we have done now is add additional columns "N" to "R" and now want to incorporate the ability to lock cells "N" to "R" for the row that has a Y in column "R".


Tried this several ways but cannot get it to lock the cells.
Note: not all rows will have a Y in column "R"

Any Help would be appreciated