A lawyer says he represents my father in a case against me but my father says he's not doing it. It's my brother, his POA.

For 25 months I served as my father designates POA and handled his finances in line with his directions. Three months ago, once my father's mental abilities declined, my brother took over a POA. My brother convinced my father that I had used his finances improperly and had a lawyer send a letter accusing conversion. I met with my father, after waiting for a lucid moment, and asked him to exaplain this to me. Without leading questions, he says that he believes me and does not want to pursue any legal action. I recorded our conversation and had a witness present. I also had my father call my brother to inform him of his wishes. What else do I need to do to protect myself from my brother? He is bent on hurting me and I am afraid that he will get to my father and persuade him to take action, when I am not there.