Poor service

I ha ve a 55inch smart tv which I received as a gift from friends that moved to the UK. So there is no proof of purchase. My tv has been constantly restarting itself making it utterly useless, trying to log a fault with Hisense to maybe just find out what the problem is, just to get told i need a proof of purchase to log a fault. Even after explaining that i do not have and can not get a proof of purchase, i just the oh well sorry we cant help you. Very very poor service, and I know for a fact that nothing will even come from writing here.