after add new details from userform to ws sort ws (column A to last row an last Column)

I am trying to adapt this code to sort worksheet "DriverDetails" by column A after an addition of information. The sub SortDetails() is called by the update macro.

It is not sorting and I cant see why. Code should take account of any number of rows and any number of columns. Data has a header row.

Function LastRow()
    Dim rowfind As Long
    rowfind = WorksheetFunction.CountA(Range("A:A"))
    LastRow = rowfind
End Function

Function LastColumn()
    Dim columnfind As Long
    columnfind = WorksheetFunction.CountA(Range("1:1"))
    LastColumn = columnfind
End Function

Sub sortdetails()
Dim sortdata
    sortdata = "A1:" & Cells(LastRow, LastColumn).Address(0, 0)

    With ActiveWorkbook.Worksheets("DriverDetails").Sort
        .SetRange Range(sortdata)
        .Header = xlYes
        .MatchCase = False
        .Orientation = xlTopToBottom
        .SortMethod = xlPinYin
        .Apply
    End With
End Sub

Any pointers appreciated....