Unable to Join Webinar Event

So I was given a link for a webinar event so I could join and I clicked on it but all it does is take me to a 'Post Attendee' page with a dialogue box that keeps loading even past the start time; and it never allows me to enter the event.  I'm not sure if I'm missing something or what but any insight would be greatly appreciated.  I have attached a picture of the dialogue box below.