> For the complete documentation index, see [llms.txt](https://docs.tryterra.co/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.tryterra.co/help-center/help-topics/no-data/connections-expiring-disconnecting/fitbit-shared-oauth-deauth-second-app.md).

# What causes a Fitbit DEAUTH event?

Fitbit allows only one active authorisation per user, so connecting the same Fitbit account through a second app **revokes the first connection and fires a `DEAUTH`** on the first app.

More generally, deauth [events](https://docs.tryterra.co/reference/health-and-fitness-api/event-types) fire when:

* The [deauthenticate endpoint](https://docs.tryterra.co/health-and-fitness-api/user-authentication) is called.
* The user revokes access in the provider's own settings.
* The token is invalidated by a re-authorisation elsewhere.