We apologies for the inconvenience this issue may have caused for you and your students. Microsoft Stream is currently not supported in the Q&A forums, the supported products are listed over here https://learn.microsoft.com/en-us/answers/products (more to be added later on).
You can find immediate help from Streams experts in the Microsoft Stream forum here:
https://techcommunity.microsoft.com/t5/microsoft-stream/ct-p/MicrosoftStream
Hope that helps.
Thanks,
Grace