If you have received a demand for payment from a collection agency, (something that I personally have never heard of), you should do the following: 1. Write to them disputing the debt and demand that they provide you with copies of the information that they are relying upon to claim you owe the money. 2. When provided with that information that should advise you as to what county-court, etc. that the ticket is out of. 3. With that information in hand go to that courthouse clerk's office and ask to verify that you in fact have the outstanding/unpaid fine. If it appears to valid you will have to make arrangements to get it paid. HOWEVER, be wary of the possibility that this is some sort of scam; district courts, in my experience, don't use collection agencies. They get your attention by defaulting you for the unpaid ticket and suspending your drivers license. When they do this it becomes impossible for someone to renew their drivers license and they are in fact driving on a suspended license.
Almost all counties in Florida use collection agencies to collect unpaid money owed on citations. It varies by county, but typically when a citation is not paid within 4-6 months then the clerk's office uses the services of a collection agency to try to get that money. I would first contact the clerk's office in the county where this ticket is pending to see if they have a copy of the citation in question. My guess is they do NOT have the citation and probably were not scanning and imaging citations 20 years ago. That leaves you with two options. Option number one would be to write a letter to the Judge handling traffic infractions in that county and see if they would be willing to get the case back on the docket. At that time you can explain to the Judge that you paid the ticket years ago and ask that the Court enter an order dismissing any additional money owed. The second option would be to just pay the ticket to the collection agency and be done with it. The downside to option two is the fact that points will probably be assessed to your driver's license. I will put a link to the DMV license check on the bottom of this post. This will allow you to check the status of your driver's license in real time.