Hi Lindsey - We also have invitees and guests who use Attendee Hub. Have you checked to make sure the invitee and the guest do not have the same email or mobile phone number entered? In our cases, that is usually what has happened, especially with the mobile phone. Also, make sure the guest's information is saved in your account's address book. I've found that when I update a guest's email or phone, I have to go through the planner modification process to ensure the guest is saved in the address book.
Good luck!
Christine
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Christine D'Arcy
Associate Director, Office of Orientation Programs | Office of Orientation Programs
University of Southern California
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