The fact that you are tolerating them being a nazi is the problem. Germans did not stop being nazis after losing WW2, they just were not allowed to express that so their children never got exposed to it. People didn’t just stop being racist, they got shamed out of expressing it, so now we don’t accept their views. Do not tolerate intolerable beliefs. If you are having a pleasant conversation about baseball with them while they are still spewing hateful beliefs, you are failing to punish them, allowing them to keep being a nazi without shame.