Hi @wschweitzer
Welcome to the LastPass Community.
When you integrate biometrics with LastPass, the device will 'unlock' the trusted app, but it does not take the place of entering the account password, which you must still do regularly to keep the status up. Logging in also creates a local user cache with which to create recovery passwords via biometrics if necessary.
If your iPhone continues to ask for the LastPass credentials every time though, then I would suggest re-installing the app to ensure it has the correct permissions.
Thank you 🙏 What do I have to do to unlock Lastpass on my iPhone using Face ID without having to enter my complicated 30-character master password? I break my fingers almost every time 😢
i've had the same issue. the article below helped. review the Enable specific actions section of this article.
https://support.lastpass.com/s/document-item?language=en_US&bundleId=lastpass&topicId=LastPass/Require_a_Password_Reprompt.html&_LANG=enus