Hi @Timo_W,
As I understand Bitwarden does not use the environment variable ADMIN_TOKEN=
See Configure Environment Variables | Bitwarden Help Center
In Bitwarden’s case the system admin portal is logged in with an email address so long as that email has been added to the environment variable adminSettings__admins=
https://bitwarden.com/help/admin-portal/
This makes me believe you are instead using Vaultwarden, which is an unofficial 3rd party fork of the Bitwarden project, but does still use compatible client apps.
You can typically verify this, as there should be some type of Vaultwarden branding in welcome emails, web-vault, or admin interface.
The Vaultwarden admin page does use the environment variable ADMIN_TOKEN= and further information can be found on the wiki here.
In short Vaultwarden will use environment variables initially, but will then ignore them once any settings are made via the admin page as it creates a config.json file which will override any environment variables you have set.
The first time you save a setting in the admin page,
config.jsonwill be generated in yourDATA_FOLDER. Values in this file will take precedence over the corresponding environment variable.
Basically you should be able to edit the config.json file to remove the admin interface, or delete the config.json file to force Vaultwarden to use environment variables, but note this file will be recreated if any variables are set with the admin interface.
Depending on your setup, you may also still wish to have the admin interface accessible, but only on your private LAN, and not be accessible on the greater internet if this is publicly exposed, this can be typically set via a reverse proxy if using HTTPS.
Please feel free to reach out directly on the Vaultwarden support forums for further help if needed. We try to keep any Vaultwarden specific concerns off of the main support unless they directly relate to the upstream project.
Hope this helps, and also directs you to the best place for this concern. 