I have an award booking, and used the AA chat feature to try to add an extra seat to my booking.

After a lengthy delay during which the agent consulted someone else on how to add an extra seat, the agent wanted to make a new reservation that includes the extra seat.

I terminated the chat session at that point as that did not sound right to me. Is it not possible for them to simply add an extra seat to my EXISTING booking?

By the way, I do not have enough miles for the extra seat, so would have to pay for the extra seat.

For those who have booked extra seats before, is the AA agent correct that she had to make a new reservation?