Trakt Plugin no longer synching

My Trakt Plugin hat stopped Synching from Kodi to Trakt as of Dec 7, on that date the last watched show has been recorded.
I tried uninstalling the plugin, reinstalling, reauthorizing, all multiple Times on my Win Desktop PC as well as on my Media Center which both dont work anymore. I dont get any error msg nor do i find an error in the kodi log (but i may be looking in the wrong place).
When i reauthorize all works as intended with one difference: In the Settings the Field which displays the Username remains empty. But when i authorize the Code Popup closes so there has to be a connection to Trakt.

I’m at a loss what else to do.

Any help is appreciated.

So by further trial an error and trying to make a log i found this in the log, maybe it helps to find the cause:
2021-01-30 16:17:31.377 T:18456 DEBUG: [script.trakt] urllib3.connectionpool: https://api.trakt.tv:443 “GET /sync/collection/movies HTTP/1.1” 423 None
2021-01-30 16:17:31.378 T:18456 WARNING: [script.trakt] trakt.interfaces.base: Request failed: “GET /sync/collection/movies” - 423: “Unknown” (Unknown)

By searching for the Error 423 in Relation to trakt I found this twitterpost:

have contacted trakt support, if that clears the problem i will mark this post as solution

Hello, I have encountered the same error. Trakt is no longer syncing in Kodi, and is not showing my Trakt username in Kodi. Also, I am not about to use the Trakt IOS APP, which I am beta testing. I have written to trakt support a few times with no response. Have you had any luck getting this fixed??

Did you guys sent a mail to support@trakt.tv ?

We still have a large backlog of support requests, apologies for it taking a while to look into it. Also keep in mind we’re not doing support over weekends which can also extend the response time.