that means that the system thinks you are doing one of this 3 things when you play live chess:
A. You abort too many games.
B. When you are losing a game you "disconect" this is to abandon the board letting the other player to be waiting for the time to run off.
C. You are sittin on the clock, this is, than in lossed games you don't move but let the time run low.
It also is telling you that if you don't fix whaever problem you have for doing this things, the system will restrict you to play more games, for example you will play only friends, or will have to wait some 5 minutes between games.
Could you please explain yo me what is the reason for that message "Your account may be restricted if you do not follow our Fair Play Policy. If restricted, you will only be able to play with friends. Please do not intentionally abort/disconnect from games or make your opponents wait unnecessarily. Thank you for keeping Chess.com a fun place to enjoy chess! "