You could start with a letter to the collection agency and include a copy of the letter from the creditor indicating the zero balance. Ask them to verify that the debt is valid.
I provide a free 15 minute telephone consult for security deposit claims and eviction defense. No attorney-client relationship is created by answering questions in this public forum. If you wish to create an attorney-client relationship, you must contact me directly and sign a representation agreement. Answers are provided based on general ideas and an answer specific to your situation would require a review of all documents.
Send them a debt dispute/validation letter and enclose the written documentation showing the charity adjustment and zero balance.
The information provided herein is general information only and not legal advice. The information provided herein does not create an attorney client relationship and is not a substitute for having a consultation with an attorney. It is important to have a consultation with an attorney as the information provided in this forum is limited and cannot possibly cover all potential issues in a given situation.
As the previous answers suggested, you can send a letter showing the zero balance. If, however, the collections company still contacts you demanding payment of the debt or negatively effects your credit reports, then you may have recourse against the debt collector. In Florida, § 559.72, Florida Statutes, provides remedies for violations of fair debt. Believe it or not, the Florida Consumer Collections Practices Act is more protective than the Federal version 15 USC 1692. It does have similar sanctions though. For instance, if the debt collector continues to try and collect the debt not due, then they can be liable for a $1,000.00 penalty and attorney's fees and costs.
If they continue to make attempts on that debt you should contact an attorney to further assist you. Sometimes a letter from an attorney detailing the requirements of 559.72, et. seq., is enough to stop all creditor harassment.