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

Costco Consumer and Costco Small Business XXXX XXXX XXXXXXXX XXXX XXXX XXXX XXXX XXXX XXXX XXXX XXXX XXXX XXXX XXXXXXXX ). Victim of Phishing. Requesting {$1100.00} XXXX credit on XXXX purchase of XXXX gift cards. 
Dear Sir / Madame : I am mortified and disheartened to write this letter and share that I have been a victim of a phishing scam. This scam essentially resulted in me buying {$1100.00} in XXXX gift cards from XXXX and sharing that information with a fake XXXX entity with the hopes of taking advantage of a 50 % off monthly bill offer. 
The way it started was I received a voicemail from a supposed XXXX agent on XX/XX/2023, enticing me to call back since they have a 50 % offer ( see Attachment XXXX Voicemail Message Screenshot XXXX XXXX XXXX ).

I called the phone number ( XXXX ) back the following day, XX/XX/2023, to learn more about the 50 % offer. Having called XXXX before to setup our mobile service, the phone prompts sounded familiar, if not the same as the real XXXX call center. 
The person on the line asked me the same questions as a XXXX agent would to verify my identity : ( 1 ) secret word ( which I did not know ). Then ( 2 ) he defaulted to asking for my last 4 digits of my Social Security Number, which I gave since its a common question. He then told me that my last monthly bill was around {$90.00}, which I affirmed to be true ( actually it was {$97.00} ), and that XXXX had an offer to cut my monthly bill by 50 %. Essentially, they had two offers : Option A - Three ( 3 ) year contract. Pay for first year up front at 50 % of monthly bill ( {$45.00} / month ). Or {$540.00} for Year 1, and then pay Year 2 and Year 3 at monthly {$45.00} rate.

Option B - Three ( 3 ) year contract. Pay for first two years up front at 50 % of monthly bill ( {$45.00} / month ). Or {$1000.00} for Year 1 and Year 2, and then pay Year 3 at monthly {$45.00} rate.

With Option B, this would include an XXXX XXXX XXXX XXXX and a {$150.00} XXXX gift card. 
Both offers were being run with XXXX and so the caveat was I had to pay with either ( 1 ) a XXXX credit card or ( 2 ) XXXX gift cards. I thought these were good deals and I was interested in Option B. However, I did not have a XXXX credit card. I asked if I could pay by regular credit card and the agent said it had to be with a XXXX credit card since it was their promotion. Furthermore, Option B was a limited time offer and I had two hours to take advantage of it. The best step for me was to secure XXXX gift cards and call them back to take advantage of Option B. Finally, to hold my spot for Option B, they will go ahead and apply a {$10.00} payment against my XXXX  account with my credit card on file. 
At this point I received a notification from my XXXX app saying a {$10.00} payment was made ( see Attachment XXXX XXXX XXXX XXXXXXXX ). 
I had no indication this transaction was fraudulent because at this point : 1. The call center sounded like an actual XXXX call center. Same prompts, same identification questions.

2. They knew my last monthly bill ( albeit it was an approximate of {$90.00}, not {$97.00} ).

3. They charged my account {$10.00} with the credit card on file, of which a notification was generated from my XXXX app. 
I ended the call and then proceeded to go to the local XXXX to buy the XXXX gift cards as suggested by the call agent. Wanting to be sure I had enough funds to cover the upfront two year bill, I bought three gift cards worth {$1100.00} ( see Attachment XXXX XXXX Gift Cards XXXX XXXX XXXX XXXX  ). Please note, the third card for {$150.00} was initially rejected by the XXXX XXXX, and hence theres a reversal and then a subsequent transaction for a different {$150.00} gift card. 
Around this time, the XXXX entity also sent an email with an invoice for {$1000.00} as discussed ( see Attachment XXXX XXXXXXXX XXXX XXXX XXXX XXXX XXXX XXXX  ). 
I called the service center back ( at a different number, XXXX ) and again heard the familiar XXXX prompts. A different agent spoke to me about the offer and asked me to provide the XXXX gift card numbers and access codes. After I shared the cards information, they told me that I would get a check for {$70.00} along with my XXXX to account for the difference between the {$1000.00} invoice and the {$1100.00} value of the gift cards. They said my account would be updated within the hour and that I would receive a text message indicating that the transaction would be complete. 
Sometime later I did receive a text message indicating that the XXXX payment I made encountered an issue and I needed to call back ( see Attachment XXXX XXXX XXXX Payment Issue ). I immediately called the number ( XXXX ) back to try to resolve. Again, I encountered the same familiar XXXX center prompts. When I finally spoke to an agent, he indicated that they could not process the XXXX gift cards because they were a different amount, {$1100.00} from the invoice amount, {$1000.00}. They suggested that they will cancel the transaction and send me a check for {$1100.00} if I provided them a new set of XXXX gift cards, {$1000.00}. They were willing to offer a lower amount, forgo {$80.00}, as a matter of courtesy for my inconvenience. I asked why they could not simply credit my account directly and it was at this point the agent yelled at me that I dont make the policy and that these were XXXX policies. 
I was taken aback by this response and lack of professionalism that at this point, I realized that I was being scammed. I challenged the agent if this transaction was legitimate and he adamantly said that it was, that I was on a recorded line and that I owed XXXX  {$1000.00}. It was at this point that I immediately hung up, afraid that Ive been a victim of an elaborate phishing scam. 
I immediately called XXXX published customer service number ( received the same prompts ) and reported the issue. The XXXX agent was apologetic about the incident and affirmed they had no XXXX promotions for 50 % off monthly bills. He acknowledged there was a {$10.00} payment made against my credit card on file and that I was likely a victim of a hack. He suggested I change my XXXX username and password, which Ive done XXXX 
I contacted Costco Citibank to report the fraudulent transaction and the customer service representative suggested that the best thing to do is to dispute the two XXXX transactions. I did this via the Citi Costco app ( reference Case XXXX XXXX and XXXX ). 
I also contacted XXXX XXXX center and they affirmed that the three gift cards ( see Attachment XXXX XXXX  Gift Cards ) had already been spent. They suggested I report the incident to our local police department and sent an e-mail acknowledging my call for a fraudulent, criminal transaction ( see Attachment XXXX XXXX Customer Report ). 
I am totally saddened and embarrassed by this incident. The next day Friday, XX/XX/2023, I went to the XXXX Police Department to report this incident ( see Attachment XXXX XXXX Police File Report ). They said there was little they can do at this point and encouraged me to contact the parties involved so they are aware of exactly what transpired. 
I am also writing to implore that the {$1100.00} XXXX transaction for XXXX gift cards be forgiven. Weve been long time customers of Costco and Citibank ; we shop exclusively with our Costco Citibank credit card and we always pay our monthly bills on time. We are loyal customers and would appreciate your understanding and leniency as weve fallen victim to this criminal act. 
Sincerely, XXXX XXXX