Cannot share Dashboard with Specific User

When I try to share dashboards with other users at my organization, it works fine.  With that being said, for some reason, when I try to share the dashboard with this specific user (whose email is in the same domain as the rest of the emails in the organization) he cannot access the dashboard.  Although it says the dashboard was successfully shared and sends him an email, he gets the error message "You do not have access to this dashboard".  When I try to type in his email address in the "Grant access to" field, autofill does not recognize him even though it recognizes other users in the organization.  The other strange thing is that with other users who I have given access it says "Can view" next to their name, while next to his name it says "Cancel invite".  How do we fix this? Thanks in advance.