Your attendee may be having issues with access, or you may need to check which ticket, add-on, or donation purchases are linked to their attendee record.
Head to Reporting > Attendees.
Click the "..." next to the attendee record.
Select Manage Purchases
This view shows paid tickets, add-ons, and donations linked to the attendee, along with useful purchase details such as restrictions, refunds, and expiry dates. You can also manually check in attendees for in-person events, remove or transfer a ticket, or assign a ticket, add-on, or donation when needed.