There isn't. The only things moderated is Campus/Pub/Walls/Forums. Scamming is also not against ToU as you send/drop things willingly. It's also not advised to openly accuse someone for scamming as it is defamation. Apologies if you were a victim but hopefully you learn from this. ?
Just warn people of trading, don’t actually say they’re a scammer because even scammers occasionally do fair trades ?