Xiaomi India — redmi note 4 short circuit and not working

Address:

Hyderabad, Andhra Pradesh, 500084

My redmi note 4 is short circuit and blasted once back from service center which is 3 month old phone. Visited service center for blank screen issue but they said need to change board which cost 11800 rs. Which should be under warranty but they put some water and said its water damage and out of warranty, now its fully not working so dont know what to do now its should be under waranty since just 3 month old.