Apple is not going to fix it, because it is not a problem with iOS 7. It is a problem with your phone or your router.
As a first step reboot your router by removing all power from it for about 15 seconds.
If that doesn't resolve the problem, and if your router still has its default SSID (network name) change it to something unique. (You should do this regardless, because even if it isn't the cause of your current problem it will be some day.)
If that doesn't resolve the problem on the phone go to Settings/General/Reset - Reset network settings.
And if that doesn't resolve it try Settings/General/Reset - Reset all settings
If it is an old router check the router manufacturer's web site for a firmware update.