I have a iPhone 3GS , but I just bought a AT&T HTC Raider/Vivid off of a friend. Everything works ,I could even make calls. but I can't connect to Internet, I get a message saying "can't connect due to APN settings" or something like that. Do I need 4g data plan, or is there anything else I can do to fix this? Im new to this stuff, thanks in advance!