If any installed app on your iPhone is creating some problem while running then there are two methods to make it working proper. First you can quit and relaunch the application, secondly delete the app from your device and install it again via App Store.
Now, through guide below you will learn the processes to make a troublesome app working back on your iPhone.
Reset iOS Apps
Double tap “Home” button on your iPhone to view all running applications. Then touch and hold the app until jiggling starts, and simply press on the button appears at the corner of your required app to quit
Double tap on “Home” button to view Home screen and from there relaunch your required app
Delete iOS App
On Home screen, touch and hold the app’s icon to which you want to delete, until jiggling starts then tap on cross button which appears at the corner of apps icon
Tap “Delete” button
Install Deleted iOS App
Tap “App Store” on home screen
Tap on “Updates” tab > “Purchased”
Scroll down to your required app, tap on cloud button associated to that app and let it install and that’s it