My iphone 4s can't connect to my internet?

I've had my iphone 4s since it was released from att its 4g and i hadnt had a problem with my internet connection until a day or two ago when i *** connect to my internet it says "wrong password" etc i've tried restartig the router but didn't help i've tried restarting my network settings but didn't work is there any other way besides trying to restore it Please i NEED BIG Help!

It's says 'wrong password', because you probably cleared browing data from your iPhone.
Check if, the password that your iPhone is using to connect to router, is actually the right password. Go to your connectivity settings, on your iPhone, and check if password is correct.