- Reset the iOS device. Nothing will be lost
Reset iOS device: Hold down the On/Off button and the Home button at the same time for at
least ten seconds, until the Apple logo appears.
- Go to Settings>General>Date&Time and make sure it is set to Automatic
- Go to Settings>wifi>the connected network and change the DNS to Google's 220.127.116.11
- Go to Settings>iTunes and App Stores and sign out and sign back in