Product: Money transfer, virtual currency, or money service

I am formally challenging the decision of USAA to find me liable for the fraudulent wire transfer that happened on XXXX XX/XX/XXXX. It is my contention that I, a XXXX USAA member XXXX was not at fault because the number used to conduct the fraud was USAAs number- as shown in the submitted evidence. Further, USAA allowed a fraudulent wire transfer of {$7800.00} from an individual who only had my Personal Identification Number ( PIN ) and no other identifying information for verification. I am to be covered under USAAs Zero Liability Policy as this was the first instance of fraud on my accounts. I formally request that USAA reopen the wire fraud case. 
On XXXX XX/XX/XXXX, I was contacted by someone calling from the USAA phone number ( ( XXXX ) XXXX ; as well, my caller ID showed USAA from my contacts which I verified ) at XXXX hours. Upon answering, I was told that there were two potential fraudulent attempts to withdraw money from my bank account. Seconds after answering the phone call, I received a text from USAA ( that I now know was from the fraudster ) that asked if I had approved a XXXX transfer of {$2000.00} to which I replied No. Having absolutely no reason to believe this was not USAA ( since the call was from the USAA number ), when asked to verify my identity, I gave the individual on the phone my USAA PIN and no other identifying information. USAA representatives regularly ask for my PIN, so I felt comfortable giving the caller my PIN. No other information was given on the phone call. Upon checking my accounts shortly after the call, I noticed that a wire transfer in the amount of {$7800.00} had been sent from my savings account. I immediately called USAA from the number in my call history that I had received earlier from whom I thought was USAA, and after multiple layers of authentication, spoke with a USAA representative who told me the wire department was closed. Since the needed department was closed, the representative submitted a wire fraud notification to the wire department. The next morning at XXXX ( approximately 17 hours after the fraudulent activity ), I called the wire transfer department as soon as they opened, and they initiated a recall. Since XXXX XX/XX/XXXX, I have spoken with numerous ( no less than 15 USAA representatives ) and have been continuously transferred to different departments, disconnected, hanged-up on, and condescended to. My accounts were locked four ( 4 ) different times since the wire fraud took place. Once was at XXXX hours at night and when I called to find out what was happening, the security/fraud department was closed. The last time they were frozen was because I had been given a temporary password and PIN earlier that morning ( when unlocking my accounts for the third time ) and when I changed them both on the USAA website at the same time as I was prompted to do, it triggered a lockdown of my accounts. During these four instances, I had no access to my accounts or the funds in them- sometimes for several hours or overnight. To make matters worse, I spoke with a customer service representative, XXXX XXXX XXXX XXXX XXXX, who told me that no one had escalated my fraud case to the correct section/department. He said he had done so and that I should have been refunded the stolen funds well before then. On XXXX XX/XX/XXXX, I was finally told that USAA would not reimburse me the funds and that it had been found that I was liable for the wire fraud, but I was not told the reasoning behind the decision. Upon calling back later that night, I spoke with XXXX XXXX XXXX XXXX in security who stated it was unusual for a claim like mine to not be reimbursed. She then stated that there were many suspicious charges on XXXX XX/XX/XXXX, ( I told her I had cleared all the charges over the phone with USAA on that day ) and then she disconnected the call ( it went to a survey at the end of the call, not a dial tone ). 
I have been with USAA for 23 years. I have been a loyal customer, having numerous loans and accounts with them over those years. As well, USAA has a Zero ( 0 ) Liability Policy, but somehow found me liable for this fraud. This was the first encounter of fraud that I have had. Furthermore, USAAs phone number was spoofed. I had no idea that I was not talking to an actual USAA representative. Later I was told that USAA representatives will never call and ask for your PIN. How am I supposed to know when and when not to give my PIN to a representative? Also, upon asking several times for the number to USAAs security or fraud department, I was told they dont have a direct line or extension by numerous USAA employees. Also, how, when armed with only my PIN ( that I admittedly had given the fraudster ) and nothing else, were they able to send a wire transfer of {$7900.00}? Is it USAAs policy to not have multiple forms of verification before wiring an amount of money that large? Should I have not been notified via text for external approval before the funds were sent? I must go through multiple layers of authentication before even talking to a customer service representative to obtain any account information over the phone, yet the someone armed only with my PIN was able to wire transfer {$7800.00}. 
I have been very vocal over the last few weeks about how unhappy I was with USAA and how they have handled this wire fraud case, and how I was going to be changing banking institutions. I also filled out a survey negatively when asked about how I felt USAA had handled my wire fraud case. To further prove this point, my social security number doesnt even work for telephonic authentication anymore- it states it is not found. It is my opinion that USAA locked my accounts four ( 4 ) times, denied me access to my funds located in their accounts by doing so, and found me liable for the fraud because, 1 ) My voicing my opinions both verbally and on a survey about their poor service and 2 ) Because USAA and its representative made several mistakes in allowing this wire fraud and in the days following. 
I have done my due diligence during this process. I have trusted USAA for many years- until I heard this case was denied. USAA has a duty to protect their USAA Member Accounts, and they failed to do so. They also failed by making this dispute a despicable, time-consuming, and grueling process. If this is not rectified, I will include my attorney in the rest of this process to assist in coming to a fair, honest result.