https://arstechnica.com/gadgets/2024/09/fitbit-apps-are-having-problems-with-syncing-accuracy/

Users of Fitbit’s iOS and Android apps have been reporting problems with the apps' ability to sync and collect and display accurate data. Some have been complaining of such problems since at least April, and Fitbit has been working on addressing syncing issues since at least September 3. However, Google's Fitbit hasn't said when it expects the bugs to be totally resolved.

On September 3, Fitbit's Status Dashboard updated to show a service disruption, pointing to an incident affecting the web API.