URGENT: JITSI MEET - The same participant is snown multiple times on the screen

Hi, I have several issues with the use of Jitsi Meet.

  1. First of all, it has happened to one participant that the window with his name was shown on the screen 6 times/8 times.
  2. The participant does not see other participants who have joined the call - only black screen appears.
  3. After clicking on the Leave button, the microphone turns off, nothing else happens.

Thanks a lot for any help!

Is this on the official https://meet.jit.si/ site or another installation somewhere else?

If it is another installation, you might have to check the notes on advanced configuration.