Passwords missing from Passwords app on iPhone

I have several apps where i log in using touch-ID, but I have lost the password

The apps do not 'show' my password even when i am logged in.

And when I search the passwords app, these passwords are not stored

I want to log into these apps from my i-pad, but cannot as I don't know the password and its not saved in my passwords app, even though its clearly saved somewhere as my touch-id works

So my question is "Where can I find password that my Touch ID unlocks, if they are not in the Passwords app?"

[Re-Titled by Moderator]