Non existant service

Hertz email services are nothing short of diabolical. I have written 5 emails to Hertz iro amounts taken off my cc after my 6 week rental, with no absolutely no response except for the automated response.. Whilst I understand there may be amounts to be paid after returning a rental vehicle such as tolls etc, I need an invoice sent to me that states what these amounts are for - but it seems Hertz simply ignores all incoming emails.