Nokia 5800 — Submitted the Nokia phone 4th time for same problem.

This is the 4th time I have submitted my phone to Nokia Care for same problem but every time the phone is returned and said to be repaired.
1st repair- submitted on 07-07-09 service job sheet number 2895
2nd repair- submitted on 14-07-09 service job sheet number[protected]/090708/35
3rd repair- submitted on 14-07-09 service job sheet number[protected]/090714/56
4th repair- submitted on 24-07-09 service job sheet number[protected]/090724/49

Problem with the phone is- phone automatically turns off with a shake or mechanical movement to it more often if I touch the phone to my palm where the screen faces down it turns off (i.e. the upper portion of screen with NOKIA logo touching my hand).
The problem has been verified by the Nokia care centre manager. (Mr. Deepak)
Ace Communication, 151, 1st Floor, Kapil Vihar, Near Metro Pillar No :-353, Main Road Pitampura, New Delhi -110034
I requested nokia to refund me the money but they refused it. After so many repairs the phone is nothing but scrap.
I have all the documents and proofs of above mentioned points and the consequences I faced.