South Bay Expressway Citation for a car I did not own at the time of violation San Diego California

I recently purchased a car on 7/20/2013.  A week later I received a citation for a toll violation that occured on 7/17/2013.  I replied to the notice stating that I did not own the car at the time of the violation and that it was not me that was driving the car.  I also sent copies of the bill of sale and other documentation that clearly states the purchase date.  Today, I get letters from the South Bay Expressway stating that they reviewed my case and said that the citation was valid and dismissal was denied.  I think it is ridiculous that my claim was denied when I sent them proof that I did not own the car at the time, and why there is no explanation as to why it was denied.  I will be calling them on Monday to request the reason as to why it was denied, also request photos of the violation to prove that it was not me nor anyone that I know that was driving.