2 weeks ago
I am sorry to hear about that.
At first please reboot your device and check date & time on your device.
Is your iOS and game fully updated?
You can try reinstalling the game. It may be caused by some corrupted download files.
If you haven't backed up your game account, don't uninstall and reinstall your game as a troubleshooting step. If you do, you could lose all the game data on your account.
Close apps running in the background. All apps that are running on your device use memory. If you can’t launch or play your game, it may not have enough memory available to run.
More troubleshooting steps can be found here:
Let us know how it went.