Redirect not working (anymore_

Hi – I had set up a developmental site for the redesign of my site and the plugin worked there as expected. I then used Duplicator into a brand new database to launch the prod site, and it’s up now https://ezit.consulting. However, the redirect to the page I’ve set up (https://ezit.consulting/404-pagemissing/) does not happen. The alert emails are sent though.

No errors in the PHP log either.
Even deactivated, deleted the plugin and newly installed from scratch. No change.

Any clue?

Thanks

https://www.ads-software.com/plugins/404-to-start/