Why does the fingerprint reader fail to unlock the Aegis door lock?

Please first make sure that the Aegis door lock and the Sentry doorbell are paired. See this FAQ. Note that both devices must be registered under the same account and the same family, and that they’re no more than about 15ft apart, as their connection is Bluetooth-based.

Assuming that at least one fingerprint has been added, please try scanning your fingerprint and check the fingerprint reader’s indicator light at the bottom:

• If the light flashed red once, then the fingerprint was not recognized. Please make sure that the fingerprint has been registered and there’s no water or sweat on the fingertip or fingerprint scanner.
• If the light did not flash, then either the fingerprint was not scanned at all, or fingerprint was recognized but no action was set. Please make sure that your finger fully touched the scanner, and also make sure that the “Unlock” option in fingerprint settings was enabled.
• If the light flashed blue once, then the fingerprint was recognized and the unlock command was issued. Please make sure that the lock is not far away from the doorbell.