Samsung S5 does not power on

So i am sitting in my living room browsing my photo's on my phone and it just shutdown in my hand with about 40% power still on battery. It would not switch back on nor charge. I took it in for repairs at Samsung repair centre century city as its less that 1year old. Because it was a warrantee claim from personal insurence, Samsung did not want to help me as there is no proof of purchase. Please assist me in pointing me in the right direction to getting my phone fixed as my job requires me to always be available 24/7or will this be the last Samsung product i will own? Or do i resort to court or media.<br>