Lenovo — Lenovo zuk z1--motherboard issue

Address:

560068

Hi im a certified customer from amazon my works fine till 8-5-2017 and then it gert started rebooting i check the issue its called a bootloop. So i cant resolve it my self i went to customer care center they took ten days to say whats the problem i repetedly contacted them to respond at last they simply told that they cant resolve the isssue it is motherboad problem and they said that your mobile has liquid damage it is not covered under warrenty and give my mobile back. So is their any thing u can do to my mobile because i even dont know when did it has liquid damage