I have a six month old puppy who has been fairly quick to learn. I've taught him the basics like sit, lay down, come, and stay as well as some more random ones like high five, touch, wave, spin, roll over, etc. He performs almost all of these flawlessly, but for some reason he is now refusing to lay down. My family's two dogs have a different cue than him so I fear I may have confused him by mixing up the cues (I accidentally started using their cues on him), but at first he responded to both cues and now he won't respond to either. Any ideas how to reteach the trick or fix my mistake in accidentally changing his cue?