Hi @Sally3cats, welcome to the community.
The date should be linked to the time zone. Have you got the automatic time zone set to on? Perhaps you could toggle it off, sync, and back on again.
- From Fitbit app dashboard, tap the Account icon

- Tap Advanced Settings.
- Turn off the Automatic time zone option.
- Tap Select time zone and select the correct time zone.
- Sync your Fitbit device.

Nathan | UK
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