Fitbit has issued several firmware updates since July that bricked the Charge 5 and several other devices. Reading the fitbit help forums is instructive, especially the complaints about the lack of response and no admission from Fitbit that there is a problem. You are behind the curve on this.
I had some issues initially with a firmware update. However, I was able to rectify them by removing the watch faces and then readding them. I noted that some of the watch faces just wouldn't seem to work. However, most of the watch faces I use work just fine. Just my two cents and thanks.
According to multiple owner reports, Fitbit's latest update for the Versa 2 has rendered some units practically useless. Believed to be a bug missed during testing, the issue leads to touchscreens no longer working in affected Versa 2 smartwatches.