Poor Customer Service - No Call back - Charges for disputed items without a phone call

So sad when a good company just can't do the basics write. Hired a Car in CPT, arrived at 9pm. Barely any light in the parking lot where i collected the car. I did the best check i could. Upon returning the car they spotted 2 small bumps in the side wall ( not near the tread ). I was then told that they have to put it through. They gave me a paper to note my comments on, which i said i will refuse to pay this as you cannot see the bumps even in broad day light. I have the photos to show this. If they expect the customer to check the vehicle to this degree they must be joking. Furthermore i have been with them for more than 10 years, you think they would have the decency to at least call me before just adding it to the invoice, as i had disputed it when signing to return the car. So i called Avis customer service when i receive the invoice, and queried the charge. They said they will have someone from CPT office call me. I said to the person on the phone that service is so lacking in south africa, that getting someone to call you back never happens............ and what do you thing has happened in the 3 days. NOTHING!!! here is my invoice details E ********** 00_ ********** 6_IN_JENKINS,DYLANMR