Q: Last year I booked an Air New Zealand Skycouch for a flight from San Francisco to Auckland, New Zealand. I'd recently had knee surgery and needed the extra room. I paid $2,170 for the ticket.

When I boarded the flight, I found out that Air New Zealand had sold two of the three adjacent seats to other passengers, and I was denied their use. The flight manager said I "hadn't paid enough" for the Skycouch option, and refused to move me to business class.

I identified myself as disabled because of my recent knee surgery. I had had stitches removed two days before flying and had promised my surgeon I could keep the leg elevated on the long flight. Because I was unable to do so, my knee swelled up so badly that my mobility was restricted and I couldn't enjoy my time in Auckland.

I originally asked Air New Zealand for my entire fare to be refunded. They declined and refunded $1,199, the difference between the normal coach fare and the Skycouch fare.

I have filed a complaint with the Department of Transportation. Do I have any other recourse to get additional compensation? For the truly traumatic and insulting way I was treated, my hope was that the airline would have done just a little bit extra.

A: It takes more than 12 hours to fly from San Francisco to Auckland. The seat pitch — a rough measure of  legroom — is somewhere between 31 and 33 inches in economy class, which makes this marathon flight an ordeal for anyone.

The Skycouch offers three economy-class seats in a row that, together, create a flexible space — an area to relax and stretch out in, or for the kids to use as a play area.

If you booked a Skycouch, you should have had one. Instead, you had to suffer through the flight in a regular economy-class seat, despite your disability.

Technically, all the airline had to do was refund you the extra money you paid. But there's still the issue of the painful crossing and how it affected your stay. Surely, Air New Zealand owes you at least an apology.

I contacted Air New Zealand. A representative explained that a schedule change in your flight time resulted in your Skycouch reservation being "disassociated" from your reservation, so Air New Zealand thought you'd paid for a single seat. A representative apologized to you, credited you with 5,000 frequent-flier miles and refunded your airfare.

Christopher Elliott is the ombudsman for National Geographic Traveler magazine. Read more tips on his blog, elliott.org or e-mail him at chris@elliott.org.