Without all the details it is impossible to say anything definitive. What is the reason for the name change ? Is it a disguised substitution of parties ? If so, that absolutely requires a Motion to Substitute Party Plaintiff and a hearing. Even if not, they cannot unilaterally make changes like that. If you don't have an attorney defending you, you need one.
Please note that the above is not intended as legal advice, it is for educational purposes only. No attorney-client relationship is created or is intended to be created hereby. You should contact a local attorney to discuss and to obtain legal advice.
Substitution of parties is governed by Fla. R. Civ. P. 1.260, which lays out the criteria for allowing a party to be substituted in a case. Genenrally, susbtitituiton is allowed if there has been a death of a party, a party has become incompetent, or if there has been a transfer in interest of the subject of the litigation from one party to another. The rule specifically states that for a transfer of interest, a substitution is made by motion.
You should seek counsel of an attorney who can review the procedural history of the case for you, and determine if the party can truly be substituted by an amendment to the complaint. The Rules suggest that this cannot happen.