Shallow man doesn’t talk to me and instantly starts attacking. Anyone knows why?

sWallow man. Unfortunately, I don't. I can;t remember if he had anything to say.

What character are you approaching him with?

Did you reply incorrectly when using the mirror?

Yeah I probably did something wrong with the mirror

Am playing as fake

If I recall correctly he'll instantly attack you if have Lohse with you.
If that's not what causing him to attack you in your current playthrough then I don't know what's causing him to be hostile, but I assume it's something you have done while exploring the island.

You should try and kill sallow man instead.

Yeah, he starts attacking if have Lohse with you. Is this the case?

I second this.

yes if she's around, he will attack. send her somewhere else if you want to talk to him first.