I’ve talked before about the American Express Platinum personal card with its current sign up bonus worth $1,025, a rebate of 102.5% of the minimum spending requirement.  Click here for the top current credit card sign up bonuses.

One of the benefits that makes the Mercedes-Benz branded version of this card the current third biggest sign up bonus is that you can get $400 worth of airline fees reimbursed by American Express in your first year of being a cardholder.

That’s because the $200 annual airline fee reimbursement is a calendar-year benefit.

For instance, I got my AMEX Platinum in November 2011. I immediately designated American Airlines as my 2011 airline for fee reimbursement and purchased three $67 gift certificates from aa.com. I received a $200 statement credit within a few days.

In January 2012, I changed my airline to United for 2012 fee reimbursement. I bought a $200 gift certificate from united.com, and again I received a $200 credit within days.

Fast forward to last month. I wrote a post about combining three strategies for a $10 out-of-pocket trip around the country. See “Triangle Award in the United States for $10 Out of Pocket.”

In it, I mentioned that I used the United gift certificate for a flight from Tampa to Washington-Dulles for $102.80. Indeed I thought I had!

But as I was checking another itinerary on united.com, I saw that TPA-IAD was listed as confirmed but not ticketed–weeks after I thought I had ticketed it.

I looked into my emails, and I found that I had received confirmation of the purchase from United.

Great! It’s “confirmed.” They’re just “processing.” Everything’s fine. Except everything wasn’t fine. I had never received a follow up e-ticket confirmation email, and I hadn’t noticed.

United never ticketed my itinerary. Nor did United alert me that there had been a problem. I would not have found out there was a problem until I signed into my account to check in if I didn’t sign into my United account almost every day.

I immediately called United. They couldn’t find my itinerary. I would have complained, but a quick search at united.com showed that the flight I wanted was now $24 cheaper. That meant that as soon I confirmed the first try hadn’t ticketed, I tried to purchase the itinerary again at the new, cheaper price.

But on my new purchase attempt, my gift card was getting error messages.

I called the support number, and it took the agent 20 minutes to reconstruct my one segment itinerary and get my gift certificate approved.

In the end, though, the phone fee was waived as it should have been since I tried to book online, and I got the flight for $79–a savings of $24.

Except…

I wrote the rest of this post about a week ago. When I wrote it, I thought my itinerary had finally been ticketed. I was wrong.

One week after I had tried for a second time to book a flight to Tampa, United called me. The agent informed me there had been a problem with my payment method–the gift card. The call was a bit mysterious.

She didn’t need any more information from me. When I told her I thought everything had been ticketed, she said, “Oh, something was put in wrong. Let me see what I can do.”

I thought she was putting me on hold, but she hung up.

Six days after that, I finally got a confirmation email that my flight was ticketed and confirmed. It now shows the same on united.com

So it only took three tries to ticket my one segment itinerary!

Recap

I had an issue with a United gift certificate I bought with my American Express Platinum card. My first attempt to purchase a flight with the gift certificate appeared to succeed, but my purchase was never ticketed.

United never contacted me about the issue, but luckily when I noticed the problem, my preferred flight was $24 cheaper.

Trying again to use my gift certificate, I received error messages online, but I eventually succeeded in using the gift certificate over the phone. Or so I thought.

A week after the second try, United called me to say that my second try had failed to ticket also. The agent said she would take care of it, and a week later, I finally got a confirmation email.

Has anyone else had problems using their airline gift certificates?

Bonus

For which current gift cards are being reimbursed as airline fees, see the American Express Membership Rewards Forum on FlyerTalk.

Here are a few threads regarding reimbursement of specific airlines. Skip to the last page for the most recent reports:

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