Sub MergeCells()
'set your data rows here
Dim Rows As Integer: Rows = 20
Dim First As Integer: First = 1
Dim Last As Integer: Last = 0
Dim Rng As Range
Application.DisplayAlerts = False
With ActiveSheet
For i = 1 To Rows + 1
If .Range("A" & i).Value <> .Range("A" & First).Value Then
If i - 1 > First Then
Last = i - 1
Set Rng = .Range("A" & First, "A" & Last)
Rng.MergeCells = True
Set Rng = .Range("B" & First, "B" & Last)
Rng.MergeCells = True
End If
First = i
Last = 0
End If
Next i
End With
Application.DisplayAlerts = True
End Sub
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