If your device has multiple Google accounts, FPse may be attempting to verify the license against an account that did not purchase the app.

If the app was installed from an external source (sideloaded), the license check will fail by design. Uninstall the current version of FPse.

A stable connection is required for the first run after an update to validate the license with Google’s servers.

Refreshing the Play Store app is the most effective fix for persistent license errors. Go to your device . Locate Google Play Store . Select Storage & cache . Tap Clear Cache , then Clear Data (or Clear Storage).