VBA Skipping lines of code.

This should be somewhat quicker

Sub namees()

   Dim Cl As Range
   Dim Ws1 As Worksheet
   Dim Ws2 As Worksheet
   
   Set Ws1 = Sheets("postcodes")
   Set Ws2 = Sheets("sheet3")
   
   With CreateObject("scripting.dictionary")
      For Each Cl In Ws1.Range("M1", Ws1.Range("M" & Rows.Count).End(xlUp))
         If Not .exists(Cl.Value) Then .Add Cl.Value, Nothing
      Next Cl
      For Each Cl In Ws2.Range("B1", Ws2.Range("B" & Rows.Count).End(xlUp))
         If .exists(Cl.Value) Then Cl.Offset(, 6).Interior.Color = 255
      Next Cl
   End With
   
End Sub