We have noted an issue with students accessing Microsoft Stream content that has been created via a Teams conference and either shared via email or embedded into Canvas.
This issue is related to the way in which students are joining the conferences and how Teams/Stream allocates permissions.
The fix is relatively painless, but does involve ticking some boxes in Stream for the vids you wish to share. If you click on the link below, you will get a video tutorial on how to resolve this issue. https://web.microsoftstream.com/video/20e36ef9-a85b-426b-aaad-58cf957b726e