The chess.com algorithm can't know the difference between cheater and a good player

Chess.com banned my friend account twice , why? because his actual elo is around 2200 but he plays against 1800's only(in his first account) and in the second account he started gaining elo from 100 and he won a bunch of games in a row and he got banned AGAIN
But you might say 'why am I so confident that he isn't cheating?'
because he has a chess channel on youtube and he tries to teach people