[solved] iCloud Contacts sync cannot complete, always stuck at 550

It starts with portions of 50 but hangs in there - anyone had similar issue to help?
Generated log file is ~29MB, but can open as notepad freezes when trying to do so.
Tried everything - restarts, repairs, generate new iCloud pass, etc., nothing…
Coming from Thundermail and using emClient for several days now and is so refreshing, like it all, just this one is bump on the road, hope can be solved so to move buying the subscription (still cannot understand biz lic so to move the whole company).
Best,
Teodor

solved.
To help those of you like myself who dont know what is wrong.
The issue was 1 contact found “corrupted” photo in it. After replacing the photo, sync completed.
How to find the corrupted contact?

  1. enable log
  2. paste it into ChatGPT asking which is the corruped card and it tells you the name (at the end of the lenghty answer)
  3. replace the photo. issue solved.

Hope will help others like myself who spent a day or two browsing and pulling hair.