Try to see their pov - there are bad actors out there that are deliberately hacking/cheating in game. They generally aren’t going to get specific and give away what Warden (or whatever they have sniffing around) finds that flags the account. Answers usually don’t deviate much from this:
You could ask (if you haven’t already) in the Customer Support forum for any guidance but I don’t hold out a lot of hope. You won’t get a list of possibilities or anything by name to search for I’m afraid.
Best of luck to you.