I think I had the case with jet2, where support for a change of a cancelled flight required my CVV, I called them and told them that I am not willing to provide

I think I had the case with jet2, where support for a change of a cancelled flight required my CVV, I called them and told them that I am not willing to provide that information and they should figure out something else. They instantly replied that I can input anything on that form and that it didn't matter and so was it.