Dont try to murder it, you might be swinging hard and fast. Relax, swing easy like you have a 7I in your hand and watch the club head hit the golf ball. If topping it sounds like you are too keen to watch where it has gone before you have completed the shot properly.
A question if I may?
Is it a top or a thin?
A top is when you drive your body passed the ball leaving the hands behind coming in steep and hitting the top of the ball. The ball is driven into the ground and bounces down the fairway
A thin is where the body stays behind the ball, causing the swing to bottom out before the ball. If you dont duff it, you'll probably catch the ball have way up sending the ball about 3 feet above the ground.
As you can imagine it's important to know which one is your shot
I would position the ball between the middle of your stance and your left heal and make sure your head stays in line with or just behind the ball at impact