Background of the issue:
I installed the WPML Learnpress Plugin so i can use WPML with Learnpress.
After installing, i noticed that no courses are shown anymore. Not on the frontend on the user on link oculto
but also not on the backend. i think the problem is that the courses are not assigned to any language, so now it looks like they don't exist anymore and the users can't see them. i also can't edit them anymore.
freshly created new courses are shown and are assigned to a language.
