A non mahram man helped a woman ,so the woman wants to give him a gift to thank him.
Can a woman give gifts to non mahram man and a man to non mahram woman?
I personally didn't know this, but this link is what I am going to source from: https://www.islamweb.net/en/fatwa/300631/on-a-woman-giving-a-gift-to-a-non-mahram-man
Basically it is permissible for the basis that there is no bad intention or any concern that would lead to anything forbidden happening.