Lenovo — In warranty refuse to resolve my problem

Address:

Muzaffarpur, Bihar, 842001

Dear team
I had purchased a mobile from online website from amazon, but i have some problem after 10 month so i had visited the service center at muzaffarpur authorised lenovo service center but when i reached there and show my handsets to technician then he told me that there is water likeage. So i called to customer care and i had requested to them that kindly open my handset and confirm that it is water likeage ya something else but he without opened the set he is double sure that there is water problem so i want to know one thing that without open the handset how he is sure about water likeage