Product: Checking or savings account

On XX/XX/XXXX, there were 6 fraudulent transactions charged from XXXX to my Citibank checking account. I reported the situation to Citibank 's dispute department and they provided provisional credit on my checking account for all 6 charges. According to them, they conducted an investigation and gave me permanent credit for 3 of the smaller charges but did not for the other 3 of the bigger charges ( {$640.00}, {$670.00}, and {$750.00} ) - this did not make sense since all the charges came from the same source. They claimed that they had sent me correspondence asking for additional information which had to be returned within a few days. I never received such letters and even if I had gotten them, I would not have made the deadline because I was in the hospital with my XXXX XXXX XXXX daughter who passed away in XXXX. Instead I received a letter which stated that they had closed the case and they would not credit my account because I did not respond to their correspondence. I called them as soon as I saw the reverse charges on my checking account and tried to explain that I did not authorize such charges and someone had hacked the XXXX account and illegally used my debit card. Citibank told me I had to submit a dispute letter explaining the situation so they would open up the case again. I faxed, mailed and email the letter on numerous dates and to summarize what the letter said - this is what I wrote : " Reference case number XXXX Citibank checking account # XXXX Dispute # XXXX, Transaction # XXXX on XX/XX/2021 in the amount of {$670.00} Dispute # XXXX, Transaction # XXXX on XX/XX/2021 in the amount of {$640.00} Dispute # XXXX, Transaction # XXXX on XX/XX/2021 in the amount of {$750.00} As stated on my letter, ( attached below ), to summarize, I, XXXX, did not authorize any of the above transactions and did not authorize anyone or any automated system to use my debit card or checking account for such transactions. I also did not receive any products, credit or anything pertaining to these transactions. My debit card was hacked and was used without my permission- this was an illegal act and whoever did it should be penalized for it. I also contacted XXXX and they agreed that these transactions were fraudulent and not made by me. I have attached XXXX 's emails for your information where they show that each transaction was accessed by an unauthorized user and their email shows that the account was compromised and can be used as proof for any claims through Citibank. Also, when I spoke to XXXX, they said that the products for these products were delivered to Maryland. I live in New York and don't know anyone who lives in Maryland. 
The letter and the XXXX emails are attached as PDF files for your viewing. '' After numerous calls to see if Citibank had received the letter plus other relevant documentation and to see what their resolution was, they told me to wait because the process could take 45 to 90 days. I received a letter regarding one of the transactions and they said that too much time has passed since this transaction and that they are not able to investigate it and would not credit the account. I wrote a second dispute letter emphasizing the fact that XXXX agreed to the account being hacked and showing each transaction and how this can be used as proof for claim by Citibank. I even tried to get XXXX to credit my checking account but they said that the banks are the ones who credit disputed transactions. 
I have also tried to get a letter from Citibank stating that these transactions were fraudulent and my account was hacked so I can file a police report, but nothing has been provided from Citibank.