I have been receiving the same message when streaming zoom to FB. I contacted the support team just, as per one post, and received this back, if t helps anyone:
Thanks for contacting Zoom Support!
For issues with live streaming to Facebook, there can be a few different causes and solutions.
Zoom does not currently support the new Facebook Live Producer feature, so if you see a notification to “try the new Live Producer” feature, please choose Dismiss to continue the live stream with their original streaming service.
Facebook made changes to their streaming service in early 2018 and now prevents some users from live streaming to groups. If you are unable to live stream your webinar to Facebook, you can configure the Facebook Live stream as a custom service as a workaround.