Invitee can't join the meeting

[DanatecOffice]

Our learner is having trouble joining the zoom meeting. They say they can't log in. They have tried with phone and personal computer. When they tried on PC, they get a message saying "Joining Meeting Timeout or Browser Restriction". When they tried on phone, the got a message saying the page does not exist.

Does anyone have any thoughts on what the problem might be? Let me know if you need any more information to assist.