Hello Matt,
I have been able to replicate this. You can tell in the popup when click the "Share" link. If a contact is using the same email as a Method user, the email address does not appear in the URL. It should contain the email address which must give permissions to log into the portal automatically. I'll put in a ticket to let developers know of this issue.
Good catch!
Greg
Greg Bilous
Community Support Specialist
Method Integration
g.bilous@method.me
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