Xiaomi India — Xiaomi redmi note 3 mobile seller

Address:

Nainital, Uttarakhand, 263148

Sir,
I have bought xiaomi redmi note 3 on 17/july/2016 from my nearest mobile seller. he is not providing cellphone bill and simply saying you will be requiring only the cell phone imei number in service centre for repairing but when i called service centre they are saying they will not accept the cellphone without bill.
I have talked about the same to the seller but he is still not providing me bill. i don't know what to do now. please guide me what i can do for it.
Imei no. [protected]