*****ulent Charges and Worst Communication

I rented a car through Hertz, OR Tambo office. I returned the car with a full tank on the 25th September 2023. A few days later my credit card was charged amounts that I was not aware of. After hours of trying to contact the company to understand the additional charges, I was informed the charges were for fuel. I informed them the car was returned with a full tank, and after days of back-and-forth communication I was told the matter will be investigated. To this day, almost a month later, I still haven't received feedback and/or my refund. The company hasn't even sent me the invoice I requested.