Solved Error: Field 'params' doesn't have a default value

I synchronized the users, that worked fine. Then did a new test and same 500 error comes.  

I also clean cache all the time. No idea if this is necessary but I do it anyway.
The diagnostic are all in green with test passed.

Joomla! version: 4.2.2
PHP version: 8.0.22
Kunena version: 6.0.2

I just made a Akeeba backup and installed this on a different server with different hosting company and everything works fine. So this is due to some email/spam setting (?) in my siteground hosting plan. If I get any detailed info from siteground why this is happening I will share the info.

ha yes I had just read something like that somewhere that could possibly be stopped by a hoster's spam filter.
I assume you have also tested with any other joomla
Global Configuration mailer settings eg php mailer or sendmail or smtp

I did test with SMTP option on a while ago when Acymailing was not working and that did not fixed the problem then but now I test again with SMTP enabled and everything works fine.

So for me the final solution is to set the Joomla mail setting to SMTP if on siteground hosting.
If on hostgator hosting the Joomla mail setting PHP mailer works fine.

Thanks for your help!