Vantiv Mercury Processing Poor service, fraudulent terms, bad to work with Cincinati Ohio

I had been a Vantiv/Mercury processing customer for about 2 years and decided to switch processors due to multiple reasons.  One of the driving factors was poor implementation originally, poor customer service and high fees.  I cancelled the account in writing and they slap me with a $495 cancellation fee, a violation of the contract.  They will not even speak to me about the dispute but sent T&C's that were not the same I signed stating that I didnt give 30 days notice to cancel.  This is completely incorrect, they are frauds, terrible to work with and would never consider Vantiv again.  Everyone should stop working with such a pathetic company and force them out of the business.