Product: Credit card or prepaid card

I am XXXX years old and live in an assisted living facility. I have been a Chase credit card holder for at least 20 years. 

On Saturday, XX/XX/XXXX, while on the way to church, I told my daughter that one of my credit cards was missing. I always keep them in the same place in my wallet, and my Chase Marriott card was missing. Several days later, on XX/XX/XXXX, after searching for and not finding my card, I called Chase to cancel it, and was told there was a balance of {$860.00} on my account. I told them I had not been using that card and they told me the charges were made on XX/XX/XXXX at two local grocery stores in the amount of {$730.00}, and {$130.00}. I immediately told them the charges were fraudulent and they cancelled that card and sent me a replacement card ending in XXXX. My assisted living then contacted the police and I filed a police theft report on XX/XX/XXXX. It is assumed that one of the assisted living staff members stole the card out of my purse and utilized it twice on XX/XX/XXXX. 

Since that time, I have been communicating with Chase at least monthly, yet they have denied my fraud claim multiple times and have even drastically lowered my available credit on my Chase United Card from {$25000.00} down to {$1400.00} due to non-payment and delinquency of the Marriot card. Chase continues to add late fees and interest to the account and after 11 months of communicating with Chase, the current balance is now at {$980.00}. 

This is a list of the dates that I have documented calls to Chase regarding these charges : XX/XX/XXXX, XX/XX/XXXX, XX/XX/XXXX, XX/XX/XXXX, XX/XX/XXXX, XX/XX/XXXX, XX/XX/XXXX, XX/XX/XXXX, XX/XX/XXXX, XX/XX/XXXX, XX/XX/XXXX, XX/XX/XXXX, XX/XX/XXXX, XX/XX/XXXX Additionally, I mailed the police report to Chase on XX/XX/XXXX, to XXXX XXXX XXXX, XXXX DE XXXX. Chase fraud states they never got the report. 
I also had a local Chase Branch fax the police report to Chase Fraud Dept on XX/XX/XXXX using fax # XXXX XXXX XXXX. Today Chase Fraud stated they never got the report. 
Today, after finding out that the Fraud Dept STILL did not have my police report, the local Chase XXXX scanned and e-mailed it once more to the Fraud Dept. 
This accounts for at least 14 calls, one direct mailing, one fax and one scan and still my Fraud Case is  being denied. I am a throat XXXX survivor and each time I call Chase agents can not hear or understand me, and I need to repeat the same information over and over again. 

What concerns me most is that Chase failed to follow the Federal Fair Credit Billing Act has ruined my credit. On XX/XX/XXXX, I received a letter from Chase stating that my line of credit on my Chase United card was decreased from {$25000.00} to {$1400.00} due to delinquency on accounts. Subsequently, my  auto ship medications were denied due to unavailable credit and I could not use my credit card to purchase medical supplies I need daily. On XX/XX/XXXX I had to have my daughter assist me with a credit review with Chase which took over 1 hour on the phone. XXXX then raised my line of credit to {$4000.00}, which is barely enough to sustain my monthly needs. 

I need help to get this issue resolved quickly. It has been going on for almost a year.