Complaint sub-issue: Credit card company isn't resolving a dispute about a purchase on your statement

On XX/XX/XXXX, I was contacted by the fraud or security department at Citi AAdvantage Card about a charge of {$230.00} that was being attempted against my credit card. An automated call asked me to verify the charge or indicate if it was fraudulent. I indicated it was fraudulent. Then I received more two text notifications that the same charge was being attempted against my credit card. Both times, I indicated that the charge was not being made by me, that it was fraudulent. I received an email warning me that the same charge was being attempted against my account. Again, I indicated that I did not authorize the charge. I received a third telephone call about the same charge. At that time, after replying again that I did not make or authorize the charge, I agreed with the Citi agent that the account should be closed and all charges to the account should be rejected. When I returned home, I cut up my existing Citi credit cards. 
Citi then sent me new credit cards with a new account number. Some time later, I received an electronic bill for my account which listed the fraudulent charge against my account, as if I had made the charge - even though the Citi security department had identified the charge as fraudulent and told me it would be stopped. I called the Citi customer service and reported the bogus charge on my account. Their agent apologized and assured me the charge would be removed. It was not removed. Weeks later, the charge was still on my account. I called again and also emailed Citi to tell them to remove the charge that they had already identified as clearly fraudulent. I was told that they would need to open an investigation into the charge. I never understood why that would be necessary. Their own security department had identified the charge as fraudulent. I had told Citi on the date of the attempted fraud that the charge was fraudulent and to close my account. They did so. Yet they continued to attempt to make me pay for the fraudulent charge. Today, I received a notice from the Citi security department telling me that they were closing the investigation, and they had ruled against my claim that the charge was not mine. This is after their own security department determined that the charge was fraudulent and closed my account to stop the fraud. I just got off the phone with yet another in a long line of Citi agents - after I screamed at him about how Citi was committing fraud in attempting to bill me for a charge that their own security people had determined ( multiple times ) was fraudulent. He asked me if I knew two people who apparently used my account number to make the charge. I told him I'd never heard of them before, and I did not authorize them to use my account. I told him I had made this clear to the Citi security department on the day of the attempted charge. This agent said he would make a note to reopen the investigation " for me. '' Reopen the investigation!!! There should never have been an investigation. I told Citi to refuse the charge the day it occurred. They should be investigating themselves. Citicards needs to be disciplined for this harassment of their customer. Other potential customers of Citicards should be warned about their anti-customer behavior.