Same problem for me. I uninstalled and reinstalled the app, and it says fitbit is unavailable. I have also tried both wifi and my data plan on my cell. Not sure what the deal is.... I did the update last night, and it worked yesterday and this morning. When I looked after 8 am is when everything stopped working.
Are we asking about the app or the Charge 3?
If your asking about the Fitbit app, see question 5 of the FAQ
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