Will not stay connected to wifi

[KevinDC5]

My brand new 3g iphone will recognize the wireless signal, but once connected only stays connected for a couple of seconds then reverts back to 3g. It worked great yesterday Help

[Hawk]

First, try toggling Airplane mode on and off and see if it helps. Rebooting is the next step, and finally, if you are still having problems, go into Settings, General, and Resets and reset network settings.
If you still have problems after that, you probably need service.