Community Moderator Alumni are previous members of the Moderation Team, which ensures conversations are friendly, factual, and on-topic. Moderators are here to answer questions, escalate bugs, and make sure your voice is heard by the larger Fitbit team. Learn more
A warm welcome to the Community @SusanLannon and thanks for troubleshooting this inconvenience by yourself. I would like to know if you keep having problems registering your sleep? If you do, I recommend restarting your Blaze a couple of times more.
Also, keep in mind that you can manually log your sleep if your tracker didn't do it by doing the following from your Fitbit app:
1. Tap the "+" icon
2. Tap Log Sleep
3. Enter your information
4. Tap Save
5. Sync
Let me know how it goes. 
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Community Moderator Alumni are previous members of the Moderation Team, which ensures conversations are friendly, factual, and on-topic. Moderators are here to answer questions, escalate bugs, and make sure your voice is heard by the larger Fitbit team. Learn more
A warm welcome to the Community @fruit_fling and @GG007 it's great to see you around.
It's weird to hear that you are receiving an error at the moment of logging your sleep, this error sometimes appear when your sleep has already been logged. Could you please double check that your sleep information is not being registered? Also, a screenshot of the error would be great.
Hope to hear from you soon.
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