“What should I do when falsely accused?”
Accusations have never been easier to spread than in the internet age. They can ruin careers, drive their victims into bankruptcy and affect the lives of family members, friends and associates in extremely unpleasant ways. Even when true, accusations are often hurled willy-nilly and frequently prosecuted with nothing remotely resembling due process or compelling evidence.
When false, you have real worst-case scenario. Good luck proving your innocence.