I am experiencing the same problem. I went through all the steps Fitbit has, if your Fitbit won't sync. One of which, was to delete it from the app (losing all unsynced data), then, set it up again, with the app. It seemed to work, for a bit, but then, it stopped syncing daily, as someone said, my first clue it wasn't syncing, was checking the time, and, my Versa was SO off, what time of day it was, it was ridiculous!
The app now says the last sync was Mon at 3:25... but, I can't be sure, if that was this week's Monday, as it doesn't put what day of the month it is, the number (I guess I could check the data, for example, see when it last recorded sleep, etc...).
The really frustrating thing, is, there is a good chance, there are multiple threads about this, because, others don't put accurate titles (ex, only stating their Fitbit won't sync... not, which Fitbit.... if it was since the update, but, they don't put that, etc...).
And, especially, that, Apple iOS, has a HUGE, red, pinned, thread, with a fix for them, having trouble syncing, after the update!!
Grrrrrrrrrrrr....
