When people say upgrading people to a rank its a 90% chance they will scam i got scammed 2 times doing this. So i think it should be bannable.
Well, people need to be careful when it comes to doing rankups. But, if they do somehow get scammed, the scammer can get banned with proper evidence.
No support. - To solve your problem, take videos or screenshots. - Don't be gullible - That's just your own fault for falling for the trick, honestly, but this isn't a good way to solve it.
Just show proof of you making the deal and if the person scams you they will get Banned because you have showed proof.