My boy is a very loving and affectionate kid however lately he keeps going to slap my in the face.

Each time I try to get him to stop or discipline he just laughs at me and try's to continue. I tell him no sternly with and without hand gestures. If I tap him on the fingers it becomes a game. I've tried just holding his arms to restrain him, but then he just kicks me. Eventually if I restrain long enough while being firm (obviously not rough) he whinges that he can't move and eventually gets bored I guess. Wondering if some mamas have any other suggestions?