A common troubleshooting step is resetting all of your apps to their factory defaults if you are having trouble with your device; your personal information will not be deleted.
1.
From the Settings app, scroll to General management.
2.
Tap General management.
3.
Scroll to Reset.
4.
Tap Reset.
5.
Tap Reset all settings.
Resetting your app preferences and settings will reset all customized settings on your phone. Personal information will not be deleted.
6.
Tap Reset settings.
7.
Tap Reset.
8.
You've completed the steps!
