Hi Yurgie,

If you hit the floor hard, your posture could be the problem, you are tilting down on your downswing. Or your swing arc is getting steep, like those of Iron play instead of a wide takeaway & wide shallow downswing of a driver.

If you are only lightly touching the floor on the downswing, it could be your ball position in relation to your stand has change, just a slight fraction can make a different.