Lenovo — touchpad not working

Address:

Patna, Bihar

Sir actully I have lenovo s850 smartphone.buying date 2 march 2015.while using my phone touchpad was working off.than m restarted the phone but problem was not solve. Than i give the phone in service center.but they were return the phone n some lier claim like ur phone is drop anywere...i asked them whts prblm in my phone but did'nt give answer...!!than take my phone and return back to home. Sir i hamblly request u plz sugest me what should i do? Phone imei no-[protected] 2-[protected]