I have a problem which happend to me several times, my opponents are resigning after several moves in correspondence chess without knowing it.
They are resigning without knowing it? That's an achievement on its own.
Doesn't sound like your problem but theirs...
This might be because the timer ran out.
No, i am playing without time and at least one of them doesnt want to quit on their onw in at least 2 games, the others quit after few moves which is unusual, i know its maybe their problem but its then messing with my statistics, even if its unrated so i want to stop it ....
What makes you believe that they do not know that they are resigning?
