Issue with selecting columns via macros

Hi everyone,

I'm working on a macro that does a fair amount of formatting & removing of columns. I've got an issue when selecting columns, instead of just selecting one column a couple are being selected but I don't understand why. Any help would be greatly appreciated.

Here's the first instance where it goes wrong, the first bit of code works fine but I've put it in so you can see that I've selected the worksheet. Instead of changing the one column to text it changes a couple of columns.

 'Copy from CSV to Quote and delete first row
    Sheets("CSV").Select
    Range("A1").Select
    Range(Selection, ActiveCell.SpecialCells(xlLastCell)).Select
    Range(Selection, Selection.End(xlToLeft)).Select
    Selection.Copy
    Sheets("Quote").Select
    Range("B12").Select
    ActiveSheet.Paste
    Range("B12").Select
    Application.CutCopyMode = False
    Selection.EntireRow.Delete
        
    'Change to text
    Columns(3).Select
    Selection.NumberFormat = "@"

Thanks
Jo