“Add card” to post no longer showing up

Hi there!
I used your plugin a lot and until now it worked flawlessly… But now the field “Create” on the post page is empty and I can’t add recipes on the post page itself. Yes, I could still do it via Create Cards > Create new card and then add a shortcode within the post, but that’s very uncomfortable and takes more time. Any idea what went wrong? Domain is slowcooker.de

Many greetings from Germany – Gabi