Once you have created a second factor, you will always need it to generate new tokens or backup TANs.
If you lose access to all your tokens, you will not be able to create new ones, and support will need to reset your tokens manually (please include your username in the support ticket).
The "backup TAN list" should always be created and printed as a separate step.
Keep the printout in a safe place for emergencies.
Create at least two separate tokens.
For more information, see: https://wiki.bwhpc.de/e/Registration/2FA