Union problem in Excel?

[pb1]

I wish to delete several columns on the same worksheet at one go. So Union was used to group those columns together. But Run-time error 1004 : Method ¡®Union¡¯ of object¡¯_Application¡¯ failed was returned.
Any way in getting around it please?

Option Explicit
Dim oExcel As Excel.Application
Dim oWB As Excel.Workbook
Dim oWS As Excel.Worksheet
 
Sub DeleteData ()
Dim rngA As Range
 
        oWB.Activate
        oWB.Sheets(2).Select
'Autofit Col
        oWB.Sheets(2).Columns ("A:L").EntireColumn.AutoFit    
        Set rngA = oExcel.Union(Columns("F"), Columns("H"))
        rngA.EntireColumn.Delete