The most common form of denial that I encounter is to insist that reductionism must be wrong. But we have countless experiments that document humans are made of particles, and that these particles obey our equations. This means that also humans, as collections of those particles, obey these equations. If you try to make room for free will by claiming humans obey other equations (or maybe no equation at all), you are implicitly claiming that particle physics is wrong. And in this case, sorry, I cannot take you seriously.
These are the typical objections that I hear, and none of them makes much sense.
I have had this discussion many times. Many people find it hard to comprehend that I do not believe in free will. And any such debate will, inevitably, be accompanied by the joke that the outcome of the argument was determined already, haha, aren’t you so original.
I have come to the conclusion that a large fraction of people are cognitively unable to question the existence of free will, and there is no argument that can change their mind.