Delta Air Lines and Northwest Airlines are now one and the same. But when Mark Steiner tried to take advantage of a price matching deal Delta offers, he was told that his Northwest flight to Phoenix didn't qualify for the program. So he wrote to Whistleblower.

Steiner e-mailed Delta several times to get an explanation and was told that only itineraries wholly operated and marketed by Delta and the Delta Connection carriers qualified for the Best Fare Guarantee.

A company representative wrote back: "While we would like to offer special consideration in cases such as yours, we are unable to honor the similar requests that we receive from others in equally deserving situations."

Later Delta wrote: "While we understand your disappointment with this decision, please respect this note as our final correspondence on the matter."

When Whistleblower inquired about the situation, Delta spokeswoman Susan Elliott said Steiner was right. On Dec. 31, the Federal Aviation Administration gave its approval for Delta Air Lines and Northwest Airlines to operate as one airline so his Northwest itinerary qualified for the deal.

Elliott said she couldn't explain how the error happened, but that Steiner would get the $100 voucher. Since each itinerary is different, she said she couldn't say whether other customers had experienced the same problem.

Have you tried to apply for Delta's Best Fare Guarantee? What do you think of price matching programs like this one?