If changing the DNS to 184.108.40.206 or 220.127.116.11 doesn't clear it up, make it a warranty issue.
Samsung's implementation can see wired work and wifi fail. You can debate it all you want but if they determine a router setting fixes it, they do charge for that. It's not a PC, smart phone or like your other devices and that really upsets folk.
My tv used to connect to the internet via our wireless router but stopped working. It eorks when hard wired but not remotely. All other devices in house also work so its not my router. The tv is the problem.