Hello! I understand that you're encountering an error message every time you open the Ad Fontes app, even when using a VPN while located in France. Let’s work together to resolve this.

First, could you please provide me with the specific error message you’re seeing? This detail will help narrow down potential causes and solutions.

In the meantime, here are a few initial troubleshooting steps you can try:

1. Restart the App: Close the app completely, then reopen it. This can sometimes clear minor glitches.

2. Clear Cache and Data:
- Go to your device's Settings.
- Select Apps or Applications.
- Find and tap on Ad Fontes.
- Tap Storage, then select Clear Cache and Clear Data.
- After this, try reopening the app.

3. Check VPN Settings: Sometimes, VPNs can cause issues if not configured correctly. Ensure you're connected to a server that is suitable for accessing the Ad Fontes app. If your VPN provides different countries/regions, try switching to another country (like the US) and reconnecting.

4. Reinstall the App: If the above steps don’t help, uninstall the Ad Fontes app and then reinstall it from the Google Play Store.

If these steps don’t resolve the issue, please let me know the specific error message you’re encountering, and I’ll be happy to help further. Are you satisfied with the initial steps I've provided?