Deny that you are a Nazi and tell them "Socialists are bad in any form."
Socialists tend to be pro-centralist, pro-government (collectivist per se). In terms of that, to a socialist, "nationalism" would mean giving to the government the ability to oppress and do all the evils of socialism. In terms of the opposition to that, the pro-individualist sees the nation as one of the many sizes of entities that protect individualism, including entity sizes of self, family, town, city, region, country, continent, world, solar system, galaxy, and universe. That became clear to me during this war because of the accusations of Nazism (by Putin against Ukraine).
(Individualism is every individual being able to decide and choose who to mate with, farm ownership, how to make income, and power over one's own destiny, using all the supercomputers of every human brain involved individually and in parallel. Socialism seeks to destroy the benefits of individualism, erasing the individual, and going against all that I just mentioned for individualism, using instead one central thug's brain for all control, which means forcing smart people to do dumb things against their will, and leads to elimination of foes and selection criteria of who is to survive.)
Basically, Nazism is bad, and there seems to be no exception to that. But the evils of socialism requires liars, and Putin is a liar.
My point in posting this is to be able to tell someone claiming you are a Nazi that you are not because you are not a socialist. When the opposition shoots back that Nazies are not socialists, then you can confidentially realize yes, they are, in whatever answer or non-answer you give as you escape the accusers. For instance, I would walk away and leave while saying "Socialists are bad in any form." Let that be their aftertaste of any such conversation!