Teams Room Meeting, camera stays black?

Hello dear community. We use in one of our conference rooms a Logitech MeetUp incl. a Logitech Tap with which we can start meetings. Unfortunately, since a few days or several weeks we have problems that when a meeting is joined or a call is started, the picture of the camera stays black. The other people in the meeting, who are connected via MacBook or whatever, see the picture of the camera, only the conference room does not. Do you as a community still have an idea what this can be due to?

LG Niels