If you are lined up correctly, to get an open club face you must be operating the hands separately from the body. Sometimes this is caused by a lateral movement in the swing. This means that you may be swaying back on your right leg on the backswing or straightening the right knee rather than keeping it flexed and braced with the weight on the inside of the right foot. Then when you return to the ball you may be swinging your body inside the target line as your weight moves forward and your hands are opening up in order to swing along the path to the ball. Usually this means that your head is moving inside the line as well before the ball is struck. Where on your left foot is the weight felt on impact? Is your head behind the ball at impact?

How is the finish of your swing? Are you balanced on the left leg and facing the target? If there is lateral movement and independent action by the arms/hands then it will show up in the finished swing. I am interested in the dynamics of your swing. Can you explain them further?