Someone Is Accusing Me Of Terrible Things, What Should I Do?

What the heck do I about this?

I loaded up a game I used to play a lot and someone keeps harassing me in the community and says he put up a post claiming I am a pedophile and that I am into horrific sexual practices. ALL are completely incorrect and does complete blasphemy on my character. I haven’t seen the post nor know what website it’s on, I don’t want to. Along with that dropping my full government name on the internet on different accounts. I have NOT been apart of this community for some time because I deemed it as very toxic and I find people who are enveloped in chronically online and lust very distasteful. This individual is very deranged and has been exposed for horrific things.

I cannot imagine why someone would do this, especially off of zero altercation or negative interaction whatsoever. I’m extremely disgusted and even more disgusted I ever even interacted with people who turned out to do these kind of things. I doubt anything will come of it because I doubt normal people are investing their time in these topics, but I don’t want to have to deal with defamation over completely empty accusations if I was involved in a later situation.

I am unknowing of what or where the post is, I have severed my connection to all things that community so I have no legal leverage if it came to be. This individual is under the age of 18, I am over the age of 18.

I have unfortunately interacted with this person before, and heard terrible things, like himself being the perpetuator of videos of animals abuse, self harm, exploitation of himself… I can imagine that a minor in this position could feel like they have nothing to lose anymore, so anything becomes a possibility, like randomly accusing someone of this.

Location: Minnesota