Have you installed your internet settings provided by your network? if not install them. You may contact your network operator for the settings or to check whether there is network at your location for Internet. You may also leave a complaint to them so that they can resolve your issue. Have tried turning OFF your phone and then turning it back ON sometimes this also works or in network settings select 4G only or 3G only or 2G only and see whether you can use the net. Sometimes the network also disconnects the net temporary try after 4 hrs then.
