Can't Connect To Video

I keep getting a message that I can't connect to video and to check my internet connection, however my connection is excellent and I'm utilizing the internet in other ways on this computer as well, so I know it's not a connection issue.

Had to cancel a session because I could not connect and the member does not have an alternative platform to speak to me on.  

Please advise when this can be resolved so I don't suffer any more loss of income.