A TikToker named Susan Berry has stumbled upon an airline hack that has helped her rake in thousands.In a viral video posted to her account this week, Berry explains that her American Airlines flight from Italy to Philadelphia is overbooked until August 15.“They need someone to volunteer to standby for the flight until then, and every day they get $1200 in travel vouchers, so now I’m up to $2400 because I did it twice,” Berry said in the video. She then asks her audience if she should stay until