I have held a Citi dividend card sinceXX/XX/XXXX with no late payments and a credit score > XXXX. I have not used it in recent years because I have switched to primarily using another card with better rewards. On this card, Citi offers quarterly bonus cash back and for XX/XX/XXXX it is 5 % off flights and hotels so I decided to use the card onXX/XX/XXXX to purchase a round trip flight from XXXX DC to XXXX for 2 people traveling XX/XX/XXXX via the booking site XX/XX/XXXX for total cost {$2000.00}. <P/>The next morning XX/XX/XXXX I received an email from the airline company indicating my card was declined but the reservation would be held for 12 hours if I would like them to charge the card again or use another card. At that point I called CitiXX/XX/XXXX @ XXXX EST to see why the card had not worked. I was told a block was placed for potential fraud because I had not used the card for quite a while. The agent told me the block would be taken off and she would include a large purchase note on the account to ensure the transaction would go through the next time. After speaking with Citi, I called the booking company to go ahead and ask the airline to charge the same card again. <P/>Later that afternoon, I receive an email from the booking company that the reservation had been cancelled by the airline. When I called to ask why, the booking company said the card was declined a second time and after a second decline, it is their policy to cancel the reservation. At this point, I would have to start a new reservation and unfortunately the flight prices had gone up {$220.00} per ticket. <P/>At this point I called CitiXX/XX/XXXX @ XXXX EST to see why the card was declined a second time. They indicated it was their employees mistake for not taking the block off ; that the large purchase note can not be used in lieu of removing the block. I then asked if they could compensate me for the airfare difference of {$440.00} since my loosing the reservation was a direct result of their mistake. The Citi manager said she was authorized to give max {$100.00} credit and together we conference called the airline XXXX directly to see if perhaps they would just charge the prior reservation even though the booking company would not- the airline would not and confirmed the tickets where indeed {$220.00} more each because there were now fewer seats on the outbound flight than there had been even 1 day ago. <P/>The Citi manager apologized and said she would give me her max allowed {$100.00} credit, which I indicated was not sufficient in this situation. Given the amount at stake was greater than the {$100.00} she was authorized to credit, I asked to speak with someone above her with a higher limit. She said there was no one available currently despite it being normal business hours but she would place a request and I would receive a call back in 24-48 hours. <P/>It has now been 4+ days and I have not received a call from Citi and in the meantime the same outbound flight is no longer available. A comparable RT ticket is now close to {$500.00} more per ticket. <P/>Citi reassured me that I could indeed use their card to complete my purchase when I called after the first decline but then they failed to take the block off resulting in a second decline and cancelation of my reservation by the merchant. When I called following the second decline, they refused to take financial accountability for their mistake and failed to follow up as they indicated they would. I called Citi again todayXX/XX/XXXX in hopes of speaking with a higher level manager and was again told that there was no one available, they would put a request in, and someone would call me in 24-48 hours which clearly did not happen last time. Of note, I also never received any fraud alert communication from Citi when my card was declined either time despite having up to date contact info on my account.