If you forget Unlock Code there is no way to recover it.
When you reset Unlock Code all data is cleared as well.
To reset Unlock Code:
1. Uninstall CardFolio app from the iOS device.
2. Install CardFolio app from the Purchased section of AppStore.
3. Don't restore old backup in iTunes before first launch of CardFolio app.
4. Launch CardFolio app and enter new Unlock Code.
5. Make a new back up in iTunes, if needed.