The Four Letter Code You Never Want To See On Your Boarding Pass
For most people this is a one-time thing, but if it happens to you regularly, there are ways to protest this happening to you, the travel expert explains, by requesting a review from the Department of Homeland Security.
Article source: https://www.huffingtonpost.co.uk/entry/four-letter-code-boarding-pass_uk_63a5ad1fe4b0d6f0b9ed0c7b