It seems that there might be some confusion with the clerk's office, unless you have another count pending (for money damages). I recommend that you contact the clerk's office to discuss this further with them.
If you have another Count pending, such as for money damages, you cannot let more than six months go by without taking action to pursue your claim. The six month period is for claims governed by Summary Procedure or Small Claims, most other cases require one year of inactivity before the case will be considered for dismissal. If you have a second count for damages, you should call the clerk's office to schedule a hearing on that claim. You will probably be before Judge Legendre if it is Osceola County. If you need guidance, you may want to pay an attorney for a consultation just to know what you should do next.
Was your eviction complaint merely for possession or did you have another count in it for money damages? I presume you were seeking damages as well since the tenant owed you funds. Were any monies ever deposited into the Court Registry by the tenant? You might want to check.
Chapter 83 requires a tenant to deposit all rent due plus amounts throughout the pendency of a case along with a written answer to avoid a default. Many times I get tenants who deposit monies, file an answer, and I still get a default because the answer does not state sufficient grounds why they should not be evicted.
It sounds like you went at this one alone and the court only closed out the possession aspect of the eviction matter. In order to go after money damages, you have to have personal "individual" service on the tenant. If the summons and complaint was just posted at the residence, then you have to go back and get the person served again. A judge is not supposed to grant a monetary judgment unless the tenant is personally served.
The notice you received is standard when a judge is trying to clear out his or her open cases. If no activity has occurred for 6 months (under summary claims procedure), or 1 full year on other matters, the judge will automatically send out a notice to dismiss for failure to prosecute. You have up to 5 days before the hearing to submit something in writing why the judge should not dismiss the action should you wish to have this matter stay open.
It might be best for you to get with a landlord/tenant attorney to discuss your matter and make sure all issues are covered.