Ok, do you think the global php version may be the problem, I’m on stable 7.4. Should I upgrade to version 8? There is no PHP Fatal error in the debug.log file. Thanks for your help.
I notice that your plugin is not yet specified as compatible with WP version 6.3.1 only up to Compatible up to version: 6.2.2. The site runs on 6.3.1. Do you think this could be the source of the problem?