Xiaomi India — mi note 6 pro mobile issue

Dear concern
I just purchased mi note 6 pro and it's not switching on after 4 months so am very disappointed and when i visited to mi service center jayanagar bangalore they are asking 9000 rs for repair the same which is under warranty also but now the mobile cost itself 12000now.

So am very unhappy with this mi phone kindly help me out on this.. Need help to get repaired my mobile without any cost because it's just 4 months old and under warranty

Regards
Gopal r
Amazon purchase id
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