Its what I call "Range Yips" It normally happens through hitting too many balls in quick succession. This can introduce swing faults like an out to in path very slowly, so it creeps up on you. The normal result is slices and shanks.

I suggest at the Range only hitting 50 balls in an hour, take a few practice swings between every ball, ALWAYS hold your follow through position and watch the ball land, this creates feedback to your brain that you need to learn. Sit down, have a coffee, think about it, watch others and see whats good or bad about their swings, learn from it.

__________________
Best Regards
Brian

________________________________
Funny o'l game!