https://support.chess.com/en/articles/8562517-how-do-i-report-someone
Public accusations are not allowed. If you suspect another member of using disallowed resources you should report them directly to staff and they will handle it if needed
Cheater
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Hello Fair Play Team,
I strongly suspect this player used an engine or outside assistance during our game. The accuracy and move timing were extremely suspicious.
I kindly ask you to investigate the account and review the game for potential fair play violations.
Thank you for your time.
[removed — MS]