Horse that has rearing problems?

When a horse is about to rear, don't let them stop! Keep making them go foreword and keep them off balance like turning their head to the side. That way they can't rear because a horse can only rear when they are balanced. I had a rearing issue with my horse too and this helped alot. You can also try hitting them on top of the head when they rear. Not hard at all, just a little pop so they realize that if they rear and go up then they get punished for it