Charles Huckabee; Progressive Insurance Agent Insurance agent did not inform me of $500 charge from rental car company. Internet

I am a 27 year old responsible homeowner, with a driving record clean as a whistle. The day before Thanksgiving, we had a major snow storm, which caused a sheet of ice on the driveway of a home we were visiting. My car lost control due to the ice and slid down the hill (out of my control). I have been with progressive since 2008 and have never made a claim until that day. Charles Huckabee, whom is the agent handling my case from the beginning was very unclear about how the process would go for me (i've never made a claim...so I needed someone to be very clear.) I drove a Chevy Tahoe (seats 8 people)I have a large family and when he told me he was setting up a rental car, I told him that I had a large family and couldn't drive anything other than an SUV...I won't fit in anything else. Weeks later Enterprise calls me and says that they still haven't received the "upgrade" acceptance from Progressive, this was the first that I heard of an upgrade. From that very first day that I explained to Mr. Huckabee that I needed an SUV, he should've explained to me that "an SUV is an upgrade, and that I would need to have it turned in in less than 30 days"that is what customer service is, explaining, making sure the customer understands...when..what..how - Especially through this process (my car's repair is taking 2 months.) I called Charles Huckabee after Enterprise called me and I was unable to reach him (I always get his voicemail, even during office hours).I never had a conversation with Charles "huck" Huckabee after that, until today. I was told to turn in my rental car on Dec 29th. Mr Huckabee even called to remind me to have the car back on Dec 29th. I retured my rental car promptly. Today there was a $500+ charge on my credit card from Enterprise, I called the rental company and they said that my insurance company never approved the "upgrade." I called Mr. Huckabee this morning about 9am, He finally returned my call at about 5pm. He told me that there was nothing he could do about the charge. I had explained to him early on that I had a spare company car that I could use when the time came to turn in the rental and that I didn't want any extra money coming out of my pocket. Mr Huckabee must have been too busy during the holiday season to explain to me, his customer - that I needed to have the car back a week early to prevent a $500+ charge to my personal account. He never told me to have the car back early. How can he get away with this?