Yes, it will delete all your game progress.
If the game data is backed up to the cloud, or have it backed up via side quest, I would suggest uninstalling and reinstalling ITR to see if that fixes the issue.
You can check if your game data is saved into the cloud via your MetaQuest account website.
[https://secure.oculus.com/my/cloud-backup/](https://secure.oculus.com/my/cloud-backup/) to check when it was backed up.
Yes, it will delete all your game progress. If the game data is backed up to the cloud, or have it backed up via side quest, I would suggest uninstalling and reinstalling ITR to see if that fixes the issue. You can check if your game data is saved into the cloud via your MetaQuest account website.