They are china company. I got a handset which seem to me repaired one(might be some one returned and they repaired repacked and supplied to me) this phone hangs up too much. Mic not good. Proximity do not work while calling. You should go to consumer court.
Here in India when govt allow other company to sell their product, govt should make a rule to make them bound to provide harass free service to the customer. If not then beat the service center guy they sometime mis-use their responsibility. Here in my city I gave left and right service center owner who is over smart.