I previously had an iCloud Photo Share album and then the pictures would stop appearing on my stream when the other member added new ones. We then removed me from the Stream to re-add. When we tried, I do not receive the invite. We tried my phone number and Apple ID. When I send the same person an invite to a "test" stream, they get the invitation right away.
I have other photo streams with other people and have not ran into any issues, just with this one person. They are able to send invites to other people for other albums as well. I am on iOS 9, they're on 8 but we had this issue when we were both on 8 as well.
Has anyone else experienced this?