Aveo 1.2 stalling on stops

Hi all,
I have Aveo 1.2 8v 2008 manual (daewoo motor same as Kalos 1.2)
I have issue with my car when I'm stopping at traffic lights or intersection (usually with 2500 or more rpm before cluch is pressed) the rpm niddle will drop to 500rpm and after 1sec (struggle) goes back to 700-800 (normal idle rpm). If AC is on the car will stall in same situation.
While I'm stopping the cluch is depressed all the way down.
Plese help, I'm having this issue for a long time and I can't figured out what is the cause.
Thank you.