Nokia 7210supernova — No any function work

I purchase Nokia 7210supernova on Aug-2009,But i not satisfied with this handset.She not work anytime properly.Five times my local nokia service center repair and three times he send Head office delhi.But no anytime she work proprely and last now he send again on 20/02/2010.
I-ST time-1 sep-2009
ii-ND time-22 dec-2009
iii rd time-27-01/2010
And now-20/02/2010.
His IMEI no is-[protected]
Please suggestion me what i do.
My contact no is-[protected]