I'm trying to create a macro that will insert a border on the bottom
row if the data in a specific column stops being duplicated and need a
hand doing it.

In one of the columns, I have data that can be duplicated and all I
need to do is to modify the existing border (dotted line grey) to a
solid black line.

So far, I've started with......

Sub InsertBorderToGroupItems()
FirstItem = ActiveCell.Value
SecondItem = ActiveCell.Offset(1,0).Value
Offsetcount = 1

Do while Activecell < ""
If FirstItem < SecondItem Then ' this is where the 2 shall differ
With ActiveCell.Offset(Offsetcount, 0)
..........

The column that its going to be checking is column "F"

However, I need the border to be inserted from Column A to Column S
(for now)
I was thinking of......

With ActiveCell.Offset(Offsetcount,0)
ActiveRow.Select
.... insert border

Any assistance would be sincerely appreciated.