A blocked tee shot is usually a shot that comes from the fear of a hook. Those that have closed club face issues usually have an overly in to out path as well. If the face to path ratio is perfect, a nice draw is the result. All is good! If that ratio is off due to a overly closed face, here comes a quick hook! After a couple of those, here comes the block!
Usually, players who block tee shots tend to play the ball too far back in their stance. Also they tend to align way too closed. I suggest aiming much more open with the ball way more forward to experience a more neutral attack.