VBA Merge Similar Cells

I would like to merge similar cells by columns, as of now I am using this macro

Sub MergeSimilarCells()

    Set myRange = Range("A1:Z300")

CheckAgain:
    For Each cell In myRange
        If cell.Value = cell.Offset(0, 1).Value And Not IsEmpty(cell) Then
            Range(cell, cell.Offset(0, 1)).Merge
            cell.VerticalAlignment = xlCenter
            cell.HorizontalAlignment = xlCenter
            GoTo CheckAgain
        End If
    Next

End Sub

My problem is with hundreds of rows and 40-50 columns, it takes forever. I am pretty sure a For Loop could help me there but I am not skilled enough to figure it out

I know the following code is wrong but I am lost

Sub SimilarCells()
  Set myRange = Range("A1:G4")
    Dim count As Integer

CheckAgain:
    count = 1

    For Each cell In myRange
        If cell.Value = cell.Offset(0, 1).Value And Not IsEmpty(cell) Then
            count = count + 1

        ElseIf cell.Value <> cell.Offset(0, 1).Value Then
            Range(cell, cell.Offset(0, -count)).Merge
        End If
    Next

End Sub

Here is what I would like to accomplish