Assuming you're erring on the open side ?
Hitting Up or Down with the Driver in an Inline Pattern - Page 14
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The ball would start high then balloon up from there.
I sprayed the face with Mark it and discovered that I was hitting low. Made some adjustments and hit towards the center. Still hit high. The mark it literature says that the teardrop pattern (slight scuff at the top) indicates that I am still hitting down. Even with the ball setup way forward I was hitting down. I flattened my swing such that the club was horizontal at the top. Still ballooning shots.
My shots feel even more solid than before they started ballooning, but I did try slowing my swing down and it did go lower. However the shots were still short.
I'm at a complete loss.
Just make sure that club head is "falling behind you" as you shallow the shaft on the downswing. Check that the club head is on or inside the hands at A6.
Note: I'm familiar with @Lihu's swing, reason for the specific advice.
I have read that only the driver, least lofted face, should be struck on upward arc. All others, even if on peg, struck with slightly downward blow. Driver, don't touch the grass and never a divot. 3w off tee, brush the grass in front of peg. 5w off tee, very short peg, clubhead slightly into the dirt, after ball departs.
I 'know' these things, find difficulty applying.