giblet

I had a flight from BKK-AMS on KLM that I upgraded with miles. When I checked in, I gave them my Delta Skymiles number and asked them to credit the flight there. It was a pretty frantic check in because we had a dog so there was a lot of other paperwork flying around. When I went to take the return flight a few months ago I noticed that the miles had been credited to my KLM account instead, and I contacted them to transfer them to Delta. They said it wasn't possible, because even though I had added my Delta account, my KLM number was still on the ticket because we had used KLM miles to upgrade. They have acknowledged that I asked to credit the miles to Delta at check-in, but said there's nothing they can do because the miles are already in my KLM account.

Here's their most recent email:

For your future reference, please be advised that once Flying Blue number is registered to your booking, there will be a highly likely possibility that your flight Miles would be credited to Flying Blue, even when you add another program's frequesnt flyer number later on.

As stated in our Terms & Conditions section 1.2.12 and 2.10, we regret to inform you again that we are unable to remove the Miles once credited. Therefore, we would like to kindly advise you to not to utilize your Flying blue number to login when making reservations or managing your booking online, as it will lead to your Flying Blue number to be associated to your reservation automatically. In addition, please note that Flying Blue number can also be added to your reservation if you mention your Flying Blue number at the time of booking, check-in or when you attempt to utilize Flying Blue member benefits such as upgrades.

Does this not seem sort of strange? Is there anything I can do, or is this a lost cause?