I've been riding him for a few months now. He's been to MANY shows, and he's about 12 years old and a great dressage horse. Never has he been like this, but now he won't trot, he won't respond to a whip, and when I use my legs and kick him or even nudge him
he slows down and does haunches in. He's a hanoverian and very big, I just don't know how to get him to go, I've noticed that his back legs are weak and that could be the cause of the problem, but I'm out of ideas. I've tried everything, and the only thing that makes him walk faster is seeing a jump, he loves them.