Fraudulent early termination fee

I fullfilled my Dish Network contract twice over & was even told that by the customer service rep when I asked to terminate my service...After returning my equipment, I was sent a statement that showed i owed nothing....a few weeks later Ireceived emails & bills requesting a $134 early termination fee...I called & after they accused me of EVERY scenario: being cut off for non payment, taking a vacation & suspending service, upgrading service, NONE of which I had done...THEN they said they had a contract from last year that I had signed (impossible)...I asked them to produce that contract & they immediately wiped the charge off my account...They still claim they "waived" the early termination fee, which I never owed to begin with...When I mention the contract they claimed they had, they NOW say they can't find it.