If you feel another member was using disallowed resources you should directly report them.
https://support.chess.com/en/articles/8562517-how-do-i-report-someone
Discussions of cheating, potential cheating, or cheat detection are not allowed in the general forums.
[removed -- MS]
People say look at your own mistakes, I get that!.
What people don't realise is, is your (supposed low ranked opponent) plays almost perfect chess for 10-15 moves and it forces those mistakes.