Seat Broken problems of the 2007 GMC Yukon

Traveling at night, at 65 miles an hour in a 2007 Yukon sle2 4 dr wagon, I hit a steer (approximately 880lbs). Upon impact, the bottom of my power driver's seat moved forward and the back of the seat tilted forward, causing me to hit the steering wheel. I had to move the seat back to get out of the vehicle. The airbags did not deploy. I reported the incident to the dealer, and my insurance agent both verbally and in writing. The vehicle had over $11,000. 00 worth of damage, but the repair center stated they were unable to find any damage to the seat. I traded the vehicle in, as I did not feel safe driving it with the seat not being replaced or repaired. The vehicle is now for sale again, and I am fearful that someone else will be in a wreck and the seat will malfunction again.