Product: Checking or savings account

On XX/XX/XXXX, while reviewing my online account at Suncoast Credit Union, I found transactions made with an XXXX payment card for a total of $.- XXXX. I attached the statement where they appear. I immediately contacted the consumer service center to see those transactions because I do not have a debit card for that account and I do not have any account with XXXX. This savings account I had only made deposits, I had never paid anything, made transfers or withdrawn money from it. 
I informed the person who helped me what had happened and she proceeded to freeze my account and told me that I had to go to a branch and there I could dispute the fraudulent transactions that had been made. At the branch they proceeded to create a new savings account for me and transfer the remaining funds to it since it was clear that someone had hacked my online account by creating two XXXX payment cards and making these transactions. 
XXXX XXXX  account specialist made a new online profile for me, changing the authorized email and passwords, and when the new accounts were ready, he closed the old ones and also cancelled the XXXX XXXX cards. When he finished with all that, I asked him what the next step was and he told me that for me that was all, that he was in charge of sending the dispute of funds from the fraudulent transactions. I asked him if I should go to the police and he told me that they XXXX XXXX XXXX were in charge of that and that I should not do anything other than wait for the resolution of my complaint. 
XXXX responded by sending me a note in my online banking, I don't know why they didn't send it to my authorized email or my authorized phone, in the note they indicate that they reviewed all the available dispute rights and determined they are unable to further assist because these transactions were made by me or by a device that I know and that I can not dispute these transactions with them< I need contac the recipient of the funds for a resolution They also tell me that I have the right to see the documents used to reach that resolution, but I have called XXXX to have access to those documents and they have not provided them to me. They told me to go to a branch, but I have gone to 3 and none of them have given me access to the documents. I think they are mock of me since they practically tell me in that note that I wanted to defraud them by making these transactions and then disputing them. 
I have tried many times to contact people from the XXXX fraud department but I only get the same response WE CAN'T DO ANYTHING FOR YOU Here on your website I have read that I have the right to the return of those funds because I did not do anything wrong as they insinuate, in addition they have trampled on my rights by denying me to see the documents with which they say the device used to make these transactions is mine or I had knowledge of this, so through you I request that Suncoast Credit Union reimburse me the money from these fraudulent transactions because their system also failed to alert me of these being that in an account where there was not even a debit card and where only deposits had been made, never withdrawals or payments, their system did not alert or saw a red flag when making all these charges of such high denomination in so few days