unauthorized mileage and paperwork alteration

Full record text

I brought my car in for a noise in my muffler. A week later the car was done and I had an extra 60-70 miles on my vehicle. When I asked them about it they told me they didnt drive my car more than maybe 3 and that was because they had to make sure the noice was gone. I had proof of the miles in and out which they tried to change on the paperwork. I asked to take a look at the cameras from when my car was in and they told me they didnt have any cameras on the outside of the building only on the inside. I find that hard to believe seeing as if someone steals a car from the lot im sure they will have to have a way to see the suspect. I then asked them if they had a recording of my call which states how many miles I had on my car when I called to make the appointment, to which their answer was also no. They told me theres nothing they can do for me and no explanations on how I had so many more miles when I picked up the car from when I dropped it off. Please make sure you write down and record your miles before and after your visit. I will not be returning for futher services.