Product: Checking or savings account

On XX/XX/XXXX a {$2000.00} fraudulent transaction done via XXXX was disbursed from my account ( at Citibank ) with out my authorization. I've tried to claim these funds back but Citibank has declined both of my claims. 
On Friday XXXX XXXX, XXXX I had a busy day and I didn't pay attention to my cell phone. After work I had an appointment at approximately XXXX pm and I rushed from work to arrive on time. After arrival I noticed that my cellphone service was operating irregularly. After about an hour my cellphone service was off. After I finished my appointment I tried for a couple of hours to get my cellphone service restored. I wasn't successful so I called the cellphone company ( XXXX ) the next day ( XX/XX/XXXX ). It wasn't until XXXX that I found that my phone number had been stolen ( ported out ). It was also on this day that I found that I was an identity theft victim. Various transactions were made from apps that I use such as XXXX XXXX XXXX, XXXX, XXXX, XXXX and numerous others. My emails were compromised and my passwords were changed. My passwords were changed on the Financial apps and checking and savings account as well. The assailant transferred {$2000.00} from a XXXX app that's attached to my Citibank online account on XX/XX/XXXX. On XXXX I spoke with both Citibank Banking and also the Credit Card division to prevent any further issues. On XX/XX/XXXX I went into the local branch ( XXXX XXXX XXXX XXXX XXXX, New York ) and XXXX XXXX ( XXXX ID : XXXX, XXXX ) a personal banker contacted the Fraud division of Citibank to claim back the fraudulent transaction to my account. I had already contacted the three Credit agencies and advised them of what happened. On XX/XX/XXXX I also filed a police report. Within a day to three days provisional credits were awarded for all of the charges except the XXXX XXXX transaction. XXXX XXXX and myself were told by the Fraud Specialist that the credit for the XXXX would post within 10 business days. 
So I waited to get my phone number back and to get the XXXX XXXX funds. Approximately the end of XXXX I received a denial letter for the XXXX reimbursment claim. It read as such : We have concluded that there are elements of your claim that lack credibility. Given the results of our investigation, we believe that the transactions that comprise your claim must considered authorized and as a result we are unable to honor it. 
i did receive my number back within a week and a half. On about XX/XX/XXXX I went to the Citibank branch near my job ( XXXX XXXX XXXX XXXX XXXX, NY ) and spoke to personal banker XXXX XXXX XXXX ( XXXX ID : XXXX phone number XXXX ). He informed me that he saw that the Fraud group were still working on my case and to wait a bit longer. So in XXXX I received another letter ( dated XXXX/XXXX/XXXX ) indicating that the previous Denial stood. I went and spoke to XXXX on about XX/XX/XXXX and he told me to disregard the two denial letters that he would follow up with the Fraud group to get the issue resolved. However when i spoke to him in XX/XX/XXXX nothing had changed. He said that he would submit another claim with my police report to help bolster my case. I haven't spoken to him since. 
I called the Fraud Department on XX/XX/XXXX and spoke with XXXX ( ID # XXXX ). she mentioned that there are only so many appeals that I could submit and that i should gather as much documented proof of Identity theft and fax it along with an appeal letter. She mentioned that the previous submissions should have had some back up ( I was never asked to provide any back up for the previous submissions with the exception of the XXXX meeting with XXXX XXXX XXXX XXXX ( he asked for the police report or Incident Information form that I provided him with ) ). So I prepared an appeal letter and gathered all of the documentation that I could gather. I was prepared to fax the documents but decided to call Citibank to confirm the fax number. It was then ( XX/XX/XXXX ) that I spoke to XXXX ( a client service supervisor ) who informed me that he has experience in resolving fraud issues and that my fax would be of no use and that I was incorrectly informed. He mentioned that the appeal would have to be done via a representative of the bank and not directly by me. 
So now I am stuck. I do not know how to proceed. I did not know what XXXX was before this issue and I do not know the person to whom this XXXX transaction was sent to. i keep my money in the bank thinking that it is safe. I feel like my money has been hijacked. I noticed that Citibank did suspect that something was wrong because they did try to contact me to confirm the transaction but I didn't notice their attempt until the next day ( XX/XX/XXXX ). However they never tried to call me. Every other institution that was impacted has cooperated and provided reimbursement. Citibank has reimbursed approximately fifteen transactions except this one. Any assistance that you can provide to resolve this issue will be appreciated.