Credit Collection Services Harassing me for a payment I do not owe

 This company keeps harassing me to make a payment on a claim that I do not owe. The letter I received states: Our client informed this office that you were involved in an incident with its insured. The above referenced amount has been placed with our office for recovery. Please be advised that the amount reflected on this notice was determined by our client based upon its investigation surrounding the incident. Any further damages incurred as a result of this incident will be added to this figure. Should this occur, you will be so advised. Then it goes into saying I should provide my insurance to pay the $2,690.58 I was involved in a disorderly conduct being in a fight with my boyfriend. And his ex- best friend claims I keyed his car of which I didn't and those charges are dismissed.. There for I'm not guilty of that "crime". Because I know the person who filed this, I talked to people who know about it and he said he used the money on his trip to Las Vegas. So he filed a false claim and now they're coming after me? I've told them this multiple times. I have showed proof of the charges being dropped yet that still harass me with letters and phone calls, because even though the charges were dismissed there apparently no proof saying I was not involved in this. I refuse to pay for someone's vacation.