How to back up and restore Samsung Secure Folder data:
1. Open the settings menu on your device.
2. Choose the Backup and restore option.
3. Select Back up Secure Folder data or Restore.
4. Select the data you want to back up or restore (photos, apps, documents, etc.).
5. Tap Back up now or Restore now to finish the process.
Please perform the clear cache of the secure folder and check if it works.
Go to Settings> Apps> Select the Secure folder app> Storage> Clear cache.
Then reboot your device once.