The store undertakes servicing of handsets, but the service in-charge does not have any about mobiles. The services are pathetic and disgusting. They lost one of the screws of my mobile and claim that it was never there.
I got my keypad changed and they offered me a fake one claiming it to be original. So, you can well understand the standard of service.
They don't take any responsibility for any damage to the mobile
Better go to the authorised service centre for your mobile. Might cost you a little more but you'll have peace of mind and assured genuine service.