Hey there Bajantaff007,
Thanks for reaching out to Apple Support Communities. We're happy to provide some assistance.
Does this only occur with WhatsApp? If so, the actions in this article may help resolve app-specific issues:
If an app on your iPhone or iPad stops responding, closes unexpectedly, or won’t open
"Close and reopen the app
Force the app to close. Then open the app to see if it works as expected.
Restart your device
Restart your iPhone or restart your iPad. Then open the app to see if it works as expected.
Check for updates
To see if updates are available for the app, open the App Store, tap your profile icon, then scroll down to see if updates are available. If updates aren't available for the app, update the software on your iPhone or iPad.
Delete the app, then redownload it
Delete the app. When you do this, you might lose data that was stored in the app. Then redownload the app. Then check to see if the problem with the app is fixed."
If the issue persists, contact the app developer to investigate:
How to contact an app developer
Have a great day!