Video is off only in Zoom

Hello community,

i reinstalled my Lenovo B50-70 with Windows 10. I installed the latest Zoom Version 6.0.11. But the Video is off. There is no picture, only a black screen but the white led close to the camera is on. When i open the camera app in Windows, there is a picture.

I checked:

- the Lenovo Vantage issue with the camera private mode - all looks good

- the Windows 10 permission for the camera - it is turned on for other apps.  Zoom is listed with the latest access

- camera driver update 

- Windows updates

Can anybody help?