First, let's check that your login options are set up correctly:
- Log in to the app with your username and password
- Go to ‘Account’ (the little cog icon at the bottom of the screen on the right).
- Check that your face/touch ID access is switched on.
If there's still an issue, this might help:
- Uninstall the app
- Restart your phone
- Reinstall the app
- Enable access to face/touch ID
- Log in again
If it’s still not working, then it might be an issue with your phone.
Your phone manufacturer might be able to help.