As I’ve said several times, unless you have a weak grip, you cannot have a flat left wrist AND a square club face (face parallel to the left arm) at the top. With a neutral or strong grip, you can have a flat left wrist and a closed face at the top or you can have a slight cup in the left wrist and a square face at the top. People obviously have differing opinions on which is best.......flat/closed or cupped/square. People do not generally recommend a weak grip, especially for the average player.