Please do the following steps:

1) Go to the App Store, go to Updates, and make sure Covet Fashion is updated to the latest version
2) Press and hold the Home button and Lock button simultaneously and keep them held down until the Apple logo appears
(a) iPhone 7 (and 7 Plus) hold down the power button on the right side of the phone, and the volume down button on the left side at the same time. Keep them held down until the phone restarts and you see the Apple logo.
(b) iPhone 8, iPhone X (and 8 Plus) Press and release the volume up button.
Press and release the volume down button.
Press and hold the side button until the screen turns off and then turns back on. You can release the side button when the Apple logo appears.
3) Start up Covet Fashion and see if the issue persists.