I side with Doc,,, slide leg is going left away from target which if you dont alter your armswing causes the ball to get away from the ankle (or the ankle away from the ball to be technical). And you are definitely on the side of the ball to early.
I agree with others too that you should get down and stay down at the foul line. You will find it easiest to accomplish if you redirect your slide at your target as this brings your weight directly overtop the foot.
You are slightly late in your pushaway about 1/2 step as well. Let the ball fall into your swinger faster.
However, You have natural timing and get through the ball at the bottom really well. Work on the above items and you will add additional power by increasing your leverage to what you already do very well.
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