That's really frustrating.... I've never had transfer issues with AMEX, Citi, or Chase. I guess Capital One may delay certain transfers for larger amounts......, although when I called Capital One they had told me that from their end it went through and perhaps it was an issue with the airline...... Ultimately thankfully the transfer went through for me on its own a few hours later (it was a Sunday, and transfer requested in the early afternoon and went through at night, so it did go through on the weekend for me). Hopefully yours goes through shortly as well....