If you drop the nose a bit and fly it faster, it will find a good glide angle. If you are trying to fly it too slow with too much elevator, it will drop the nose when it stalls, pick up speed, which will raise the nose, and it will stall again. You need to fly it faster. The only way to do that is not hold the nose up so much. If your CG is way off, it will hunt more too. It should pull gently out of a shallow dive if it is ballanced right.