This is because you logged out of the App.
Next time you try to get in, your details would not be recognised as if there was a previous session, so you would be asked for the OTP, the passcode and then you would be asked to allow biometrics to log in easily next time. These preferences, would be reset every time you log out from the App.
Logging out is useful in case you need to log in into a different WeSwap account or if you are using a different device, otherwise, we'd suggest to leave the App in the background without logging out- the session would expire after a few minutes.
Once you try to log in again, you would be able to use biometrics (if previously set it up) or enter your passcode since your details would be remembered in the app.