All of the suggestions above require a computer. From my understanding of the problem I would be amazed if there was a way of fixing it without. If you don't have access to a computer I suggest talking to someone who has.
Personally unless I had bought a phone knowing it wasn't working I would want my money back. But on the other hand if someone was selling an S8 at that price it had to be either faulty, bricked, blacklisted, stolen or a fake phone - that's way too low a price for a legitimate S8 in good working order.
Personally unless I had bought a phone knowing it wasn't working I would want my money back. But on the other hand if someone was selling an S8 at that price it had to be either faulty, bricked, blacklisted, stolen or a fake phone - that's way too low a price for a legitimate S8 in good working order.