Concatenating issue with code

hi,

I have a situation wherein cell content in column A is same but they are not joined as expected with my code:-

Sub mergenumbers()
    Dim lngRow As Long

    With ActiveSheet
        Dim columnToMatch As Integer: columnToMatch = 1
        Dim columnToConcatenate As Integer: columnToConcatenate = 2
        

        lngRow = .Cells(65536, columnToMatch).End(xlUp).Row
        .Cells(columnToMatch).CurrentRegion.Sort key1:=.Cells(columnToMatch), Header:=xlYes

        Do
            If .Cells(lngRow, columnToMatch) = .Cells(lngRow - 1, columnToMatch) Then
                .Cells(lngRow - 1, columnToConcatenate) = .Cells(lngRow - 1, columnToConcatenate) & vbCrLf & .Cells(lngRow, columnToConcatenate)
                .Rows(lngRow).Delete
            End If

            lngRow = lngRow - 1
        Loop Until lngRow = 1
    End With
End Sub

i am not sure but something is wrong with the cell content format? Am i missing something here? attached is sheet to test.