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i got warned for letting my time run out instead of resigning

but i was winningg at the game and it was 5+0 it says i can get banned because of this
It's just a warning. If you don't make a habit of it, nothing will happen.
I couldn't find a game where you lost on time but were winning.

But I found quite a lot of games that you were just throwing, so I think you better start to read the TOS *very* carefully ASAP.