Lesson- Don't say anything at all, just walk away quietly and keep saying "La Ilaha Il Allah" in you heart ;D - Remember, only in your heart, otherwise you could face even more islamaphobia. - As well as this, do not reply back rudely as our Prophet Muhammad ﷺ was most patient, and did not in his whole life, say anything back mocking them or their own religion.
-Me -Scratch -And most of all, Allah (S.W.T)