NOKIA 7610 supernova
Phone not working properly

I PURCHSED NOKIA CELL MODEL 7610 SUPERNOVA IMEI NO 356388027773034.

I WANT TO TELL YOU THAT FROM SECOND DAY I AM HAVING LOTS OF PROBLEMS FROM THIS MOBILE, LIKE KEYS DONT WORK, CANN'T SWICTH ON PHONE AND SOFTWARE PROBLEMS. I TOOK THIS PHONE MANY TIME TO SERVICE CENTRE AND SUMMITED TWO TIMESIN SERVICE CENTRE. I AM VERY UNHAPPY WITH THIS, PLEASE HELP ME TO CHANGE MY HAND SET.

RAVINDER SINGH