it takes practice. Find your biggest hater and figure out a way to see things from their point of view. Get them to either like you or block you. Either way, they won’t forget you. Occasionally, someone will block me for being nice to them.
(not fake nice either – I genuinely care about people who are only a few words on a screen – I KNOW there’s a real person on the other end who is lonely and decided to engage with me, even as a hater)
Sometimes they surprise me. They change their ways. Even those who can’t stand me being nice and block me will unblock me a year or two later and apologize. I believe most people are basically good but they never learned how to be a friend properly. I try to show them by example.