I upgraded Joomla to Version 4 and re-installed CComment. Comments and settings were still there but it the front-end I get the following error when trying to submit a new comment.

'We are sorry but something went wrong with your request. Try again and if it doesn't work notify the system administrator. '

I tried various things: Emulate Bootstrap yes/no, Caching all off... Nothing worked

Any idea what could be wrong.