If you have a reverse pivot problem in your golf swing, as you swing the golf club back away from the ball on your backswing, you will incorrectly put more weight on to your left foot at the top of your backswing (for a right handed golfer).
This will result in a spine angle where the upper part of your spine is closer to the target than the lower part of your spine and again this is an incorrect position. The result of this position at the top of your backswing will be that you either making a chopping action with the golf club down towards the ball and strike the top of the ball into the floor producing a low shot with little power, or you will try to correct the position and your weight will move back on to your right foot as you swing down towards the ball, which will result in you leaning to the right with your body as you hit, making you strike the ground before the ball or just skim over the ground and catching the ball as you swing upwards, again hitting the top of the ball. Either way, a reverse pivot makes it very difficult to strike the ball consistently well or with any power.
To correct this position at the top of your backswing, try this drill. Set up ready to hit the golf ball. Imagine you have a friend standing to the right of you, in line with you but with a waist height fence between you. Reach out to them with your left hand as though you were going to shake their hand over the fence. This movement will now put you into a position where you have transferred your weight on to your right foot and moved your upper spine slightly over to the right of your lower spine, which is the correct position to be in.
Similarly, you could hold a resistance band in your hands as though it were your golf club. Place the other end of the band under your left foot and stretch the band away to your right as you make your backswing, holding it out away from you.
This will also create the same position where you have moved your weight over to your right foot and your upper spine to the right of your lower spine as you have rotated your shoulders 90 degrees to the right.