[Geschlossen] Fixing 404 error for translated pages

Background of the issue:
I have translated some of the pages of my website versteckter Link using WPML and added a language switch. I use Elementor to edit pages and have updated WPML plugins, cleared caches, and saved permalinks.

Symptoms:
I mostly get a 404 error page when trying to access translated pages, although sometimes the translated page loads correctly for example on this page: versteckter Link

Questions:
How can I fix the 404 error for translated pages?