Hi inmyrvm,
Thanks for letting us know. Just to confirm, is YouTube the only affected app? If so, try going through these steps here, testing after each step: If an app unexpectedly quits, stops responding, or won’t open. These steps can help troubleshoot the app itself and it may resolve how it reports to Screen Time. We have pasted the step below for your convenience:
"1) Quit and reopen the app
Quit the app, then open it again. If the app won't quit, force the app to quit. Then check to see if the problem with the app is fixed.
2) Restart your Mac
Restart your Mac. Then check to see if the problem with the app is fixed.
3) Check for updates
To see if updates are available for the app, open the App Store, then click Updates. If updates aren't available for the app, update the software on your Mac. Or if you didn't get the app from the App Store, look for updates to the app on the app developer's website. Then check to see if the problem with the app is fixed.
4) Reinstall the app
Delete the app. When you do this, you might lose data that was stored in the app. Then redownload the app. If you didn't get the app from the App Store, redownload the app on the app developer's website. Then check to see if the problem with the app is fixed."
Keep us updated!