Hi;

A good player challenged me to a rematch, but I discovered after accepting that he had chosen to play as White even though he was White in the previous game, so I aborted the game thinking that he had made a genuine oversight, so as to send him a challenge with me as White...

However, I got a message saying that he was still allowed to move within the given time limit.  Somehow the 'system' thinks that the first challenge is still live and wasn't aborted - in the meantime the other player is probably wondering why I aborted...

please submit a support ticket on this issue and we'll look into it!

http://support.chess.com