All horses at some point in time need to be returned to the basics. Your horse sounds like it requires some re-schooling in the art of giving to the bit. You need to practice exercises that increase the responding to the bit.
Light hands are extremely important.
I have found an excellent book and training video that is by Vern Sapergia called Step by Step Progressive Horse Training. All horses at some point in time need to be returned to the basics. Your horse sounds like it requires some re-schooling in the art of giving to the bit. You need to practice exercises that increase the responding to the bit.