How do I get permission to view quarantined messages for a group mailbox?

I was added to an Outlook group through the Exchange admin center. If a quarantine mail comes in from email address removed for privacy reasons and I want to click on "Check message", I am redirected to the quarantine website, but I get the message "You do not have the necessary permission to perform this process." I can't delete or release quarantined messages as a result. I don't even see the messages. I am both a member and owner of the group. Does anyone have a solution for this?

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