206 HDi Key Problem

Hello friends, I am disturbing you for a small and important problem in my new car. There is a problem with my car's key with normal remote locking and unlocking, it unlocks the car while unlocking it, but when it is locked, it locks and auto-back. Why can this happen and the iron side of this key is pretty rusty?

Sir, the problem is not in the key, in the locks of the doors, the vehicle does not detect that one of the doors is closed, and when you lock it back it opens. Move the car interior headlamp to the door position and start the car and move on. If the beacon flashes, the problem is in lock.

Most likely it is on the lock, teacher, then what is the cost of the new key? the vehicle has an immobilizer.

My teacher changes from service to service I made it 5-6 months ago, I got price from 3 services, except for metal tip, they gave 270-220 and 192 TL price. 192 service to immobilzer chip control circuit and control container (excluding tip was 20 TL) `` I made it.