The only way that I can see this happening...is if someone said "Hey, I'm going on vacation. Even though you don't know me very well, could you enter this information into your account & password...so you can log into My Account and make sure on one steals my stuff/deletes my account? Thanks" MUhahahahaaaaa. OR "Hey, you want to play a really high character? Just to see how it works? I have an extra account! Give me your account name & password and you'll be able to play my high level character!"
Either scenario...don't trust them. If you do, you get what you deserve, IMHO. I guess I don't curry favour to people who've been warned about online scams and accounts being hacked...but then do dumb things and then complain that they did a dumb thing.
TQQdles™