If you are a Teacher, and signed in with your HPA googgle account, and still getting a message saying that youtube video is restricted and to contact your network Administrator, read below for a possible fix.
This applies specifically to HPA Teachers/Staff, not students.
Use the link below, and watch the video. It shows step by step instrutions on what should resolve this issue for you.
(FYI, there is no audio in the video)
https://drive.google.com/file/d/1m5vabzrFdYlmfUckgrO4wHvcIGVvAwOh/view?usp=sharing
(If the above link is not working for you, make sure you are signed in to google with youe HPA Google account, as it is only avaiable to Teachers/Staff.)