Alarm problems

Hello everyone, I apologize if I am wrong about the forum and thanks for reading this request: I have a 2002 Pointer City which collided with me on the back of the right side and as a consequence the rear door is discouraged and therefore I could not activate the original alarm, I sent it to repair but the problem of the alarm continues, if someone could inform me how to solve this problem I would appreciate them enough.

What is the problem you have?