@Allison_Masching Hi, there isn't a set time on how long this should take, Microsoft does say it can take a while depending on different factors, this can include behind the scenes issues like capacity and so forth.
https://docs.microsoft.com/en-us/stream/upload-process-overview
This issue does seem to pop up from time to time as noted below. If it continues, I'd log a service request with Microsoft if you have access to that or just give it more time, after which it should go through.
https://techcommunity.microsoft.com/t5/microsoft-stream-forum/stuck-at-0-processing/m-p/203312
