Similar Internet problems, tried allowing all the app lots of permissions, nothing, tried reset buttons, nothing, tried clearing cache and memory, nothing, I just know if I go to the O2 shop, no-one will have a clue and say it's a Samsung problem. Technology is great until it doesn't work and the know one has a clue. People will give you little pointers, but noone really has a clue. Accept your fate. Best thing is when you get a new phone, do nothing.