Macro Needed to Concatenate Data in separate ROWS

Too may characters in one cell to dump the results in one go

Sub testToOtherSheet()
    Dim a, i As Long, n As Long
    With Sheets("1")
        a = .Range("a1", .Range("a" & Rows.Count).End(xlUp)).Resize(, 2).Value
    End With
    With CreateObject("Scripting.Dictionary")
        .CompareMode = 1
        For i = 1 To UBound(a, 1)
            If a(i, 1) <> "" Then
                If Not .exists(a(i, 1)) Then
                    .Item(a(i, 1)) = .Count + 1
                    a(.Item(a(i, 1)), 1) = a(i, 1)
                    a(.Item(a(i, 1)), 2) = a(i, 2)
                Else
                    a(.Item(a(i, 1)), 2) = _
                    Join(Array(a(.Item(a(i, 1)), 2), a(i, 2)), "-")
                End If
            End If
        Next
        n = .Count
    End With
    With Sheets("2").Cells(1)
        .CurrentRegion.ClearContents
        For i = 1 To n
            .Cells(i, 1).Value = a(i, 1)
            .Cells(i, 2).Value = a(i, 2)
        Next
    End With
End Sub