Dell India — provided wrong service center by dell authorised exclusive store

Address:

Patna, Bihar, 800013

I visited to dell authorised exclusive store for asking service center of dell cuz i can't located the address. The given address of service center by dell is unauthorised service center. They told me that this is authorised service center of dell and they ruined my alien ware laptop. Now i can't extend my warranty and they something inject in my bios. Kindly take action for providing wrong detail and help me for exchanging my laptop. For this i shall be very thankful to you.