Do a restart (even if you have to hold the power button for 10 seconds). Because at initial boot state, the contents of your phone are encrypted. Any unlocks after the initial unlock, your phone is decrypted and the key is in RAM. Only a password/pin (no fingerprint/FaceID/etc) can be used to decrypt your data.
In lockdown mode, my understanding is that you’re simply disabling biometrics (but not encrypting anything).
Thank you. I say it because I was genuinely asking the person who replied to me, in case I was wrong. In the context of privacy, it’s extremely important to know for sure.