My iPhone 4 never connects to wireless?

My iPhone 4 never connects to my wireless Internet I have at home. I often go to settings and type it in, but it says "could not find the network". I was wondering, how do you fix this so I don't use all my data? Also does anyone else have this problem?

Maybe it's has something to do with the router you have. Or you can type the network manually.

Try unplugging router.wait thirty seconds then plug it back in. While router is unplugged restart phone.