I was wondering how to insert data (numbers) from a combobox into a spreadsheet underneath the column specified by a different combobox, which is a text. For instance, I have one combobox in which the user selects a customer, and another combobox where the user enters a part number. The customer names are in the first row of a sheet and I want the part numbers to appear below that customer name chosen, by smallest to largest and underneath the already present part #'s. As of now I have this, but I know it's wrong.
        idx = ComboBox1.Text
        
        Set rngParts = .Range(.Cells(2, idx + 1), .Cells(LastRow, idx + 1))
    
        With Sheets("Metallize")
            Unload NewPartNumUF
            Sheets("Metallize").Select
            RowNum = .Cells(Rows.Count, 1).End(xlUp).Offset(1, 0).Row

            Cells(RowNum, idx) = TextBox1.Value
        
            Unload NewPartNumUF
            Worksheets("Metallize").Activate
        End With