How to make working butterfly wings?

My brother's Syma S107 helicopter isn't working. What's wrong?

• My little brother was so excited about this new Syma S107 radio-controlled helicopter my dad bought for him. However, about 3 weeks in it started making this screeeeeeching noise, and the 2nd pair of wings (the one on the bottom) didn't work anymore but if you pushed the nozzle up long enough, they would begin rotating. I thought the first pair of wings was working fine but after a lot of tinkering I found out that it was the one making the screeching noise. What I don't understand is why the heli won't get up off the ground, because after a while both wings are rotating. But the helicopter just spins around and around on the surface and continues to make the screeching sound... also, a few days before we noticed this, I landed the copter on the sofa upside down and accidentally continued to hold up the nozzle so the wings really beat into the sofa. It's more because of my brother, I would love to see him playing with it again. So what's the cause of the screeching and not getting up off the ground, and how do you fix it? Any heli enthusiast who could help us out, I'd be really thankful.

• Answer:

  the blue and red wireing is not connected or the yellow and blue wire is not connected