Good afternoon jamvinl,
Welcome to the Apple Support Communities!
It sounds like you are not able to see passwords for some apps, and we'd like to help.
How many apps are you missing passwords for?
While you are still able to access them via Face ID, it may be helpful to go into the account settings for the app and reset the password so that you'll have it.
Here are some general resources for working with passwords:
Make your passwords available on all your devices with iPhone and iCloud Keychain - iPhone User Guide
Using app-specific passwords
Take care.