Add an attendee without email address, but linked to another attendee record

An Attendee with the name Albert had pre-registered on the event website. He had entered his name and email address, but he had not yet bought a ticket. At the door of the Venue, he bought 2 tickets and paid cash.

I was able to add one ticket to his Attendee record, but I cannot add two of the same tickets to him. I don't know the email address of the second person, so I am unable to create an Attendee Record for her.

If Albert would have bought 2 tickets on the website, he would have been able to buy two identical tickets. He will be asked to add the name and email address of the second Attendee. After this he can pay for both Attendees in one transaction.

I am not able to do this in the backend. It would be better if I could add the second Attendee and link this purchase to the first one, without the need to enter an email address.

PS

I talked with another Attendee at the event yesterday (Hans). He has purchased two identical tickets. He told he had to enter the name and email address of the second attendee (Laura). He confirmed that she never received any emails and that he only received emails related to his own tickets.

We don’t receive the name and email address of the second attendee. We see two entries in the Sales Report, both with the name and email address of the buyer.

I have sent an email to support about this with screenshots. For privacy reasons I don’t repeat this here.