Product: Checking or savings account

XXXX XXXX I saw that 30 DAILY fraudulent withdrawals from ATM in XXXX occurred, beginning XXXX XXXX from my savings account, totaling {$15000.00}. 
Although I have a wonderful history with Citibank on XXXX XXXX spanning 4 decades, accounts, mortgages etc. they have dropped the ball and have thrice declined my request to be reimbursed for this fraudulent mess. They have unbelievably stated to me - Based on investigation. ( they have done none ) this atm card belonged to me and MY pin number was used- further, it seems to be my usual banking activity. '' None of that is valid.In fact, They never contacted me when suddenly {$500.00} is taken multiple times a day from a machine across the world. 

This statement from them is ALL INSANE. 
It was NOT my card, citibank sent it to XXXX, The card was in XXXX 's name- also, I do NOT use my Atm Card to get cash.. 
I was in America, and my personal card in my possession, and they can see this if they actually look at my banking history.. There is no manager or case worker handling this, each time I call, I get transferred 5 times, and the last call was 90 minutes with ZERO results. 

History : My previous dear friend/partner. XXXX had returned to XXXX and later became ill and died XX/XX/XXXX. After that time, I contacted citibank to see if any of our accounts were linked, they could find NONE. They told me without a death certificate they could not close her check account..

( social security checks were being deposited. ) .I gave up, there wasnt anything I could do.

I did NOT realize that she was a co signer on my savings account, it had been inactive for years. Her son and wife ( elder abusers ) and sister had access to her citicard and pin number. I know that Citibank knew her address in XXXX as she had gotten a card sent there in the past. It is entirely possible they even sent a new card with family impersonating her to order the card.. Clearly they did not want the social security money to stop which, to my knowledge is still being deposited into her account and accessed by surviving son. I had no way to reach this family and they do not speak english. 
During this crazy daily withdrawal of $ XXXX {$1000.00} a day, Citibank never tried to alert me or question this UNUSUAL activity. I have, in the past, been questioned on charges as small as {$30.00} when it seemed unusual activity-To first show that She died, I have sent them numerous references to social media in America AND XXXX showing that XXXX passed. Police wont do anything because it is out of their jurisdiction I am sure XXXX police dont care, and this crime is being ignored. 

If anyone cared, the person who did these withdrawals is on camera at the same atm in XXXX over and over day after day, But no one cares to do that. They just want ME to suffer this {$15000.00} loss and I am XXXX years old and my only income is a small social security check. Please I need your help to push on Citibank to do the right thing. 
This {$15000.00} was not even mine, but belongs to a sick sister who needs it to pay her taxes. How will I give it to her? I lost my income for the entire year of XXXX and have no idea about future. I have contacted XXXX XXXX XXXX, the Police in Florida, The NYS dept of Financial Services, and the Office of the Comptroller of the Currency and they ALL tell me this is out of their jurisdiction. I need help ...