WD Sync on Mac does not work

I have been trying to get WD sync running for quite a while, now. Unfortunately without success.
First issue is that the initialization is always incomplete
Then it usually works - not reliably - for 1 or 2 weeks and
finally it stops synchronizing completely.
There is never an error message (report is synchronization is complete), but the tool simply does not synchronize the files.

Being German, I have some files with ä, ö, ß and so on and since I live in Japan, also Japanese file names and Korean file names exist on my HD. I sure hope that this is not the issue.

Please give me some advise, how I get the software running.
Thank you in advance

Hi sgeis77,

You can have a look on below KBA in this concern: