Room not found after creation

[lrit18]

Hello everybody,
I'm trying to create and use a room with the plugin. I can create the room with the plugin. But if I go to the created page https: //www.xxxxx.xx/bbb-room/myroom/ nothing is displayed there. I get a message from wordpress that the page could not be found. However, the room is displayed in the overview in the backend.
I use the newest WordPress version 5.7 (instead of tested 5.3.6).
Is there someone who has an idea and can help me. Many Thanks

[hostbbb]

Some rooms are working right? Im debugging similar right now on 2.4.4. BBB. Can you confirm if some work, and your BBB version