If you believe in the unconscious mind, or one of its many permutations, subconscious, non-conscious, pre-conscious, extra-conscious, (and maybe even cognitive schemas or implicit memory), if you believe that any of your thoughts, emotions, or behaviors are caused by or motivated by factors of which you are not aware (and if you don’t, let me know and I’ll send you a week’s worth of reading, research showing you are almost certainly wrong), then you cannot rationally believe that you have free will, because even if you did have free will, you could never know it. There will always be that possibility that each action you take is guided by something that is not your will. You can still believe that you might have free will, and you might,* but not that you do have free will.

*In fact, you may be better off pretending that you do.