Carfax reports useless

Carfax provide a erroneous report to me when I bought my used car. Five years later, when I attempted to trade my car, the dealer offered me $2,500 less than the book value because of an undisclosed second accident that was not reported in the initial report, but showed up in the most recent report. Carfax refused to acknowledge responsibility and offered no compensation for my loss. Carfax reports are useless and Carfax is committing fraud in selling them.