Air Bag Not Deploy problems of the 2004 Lincoln Navigator

I bought my one owner carfax incident free 2004 Lincoln Navigator in April 2009 , in may 2009 I was driving down the highway and my side curtain airbags deployed almost causing me to wreck my vehicle, the truck was taken to the dealer where purchased , after waiting over a week the truck was returned with no explanation the only thing I was told was that it did not fall under warranty and they would not be willing to help. Left with no option, I am driving the vehicle as is, I was not given any information or warnings. While driving the vehicle again on 5/24 the drivers airbag fired but did not deploy, again almost causing an accident. I am currently taking the vehicle to get the airbags turned off.

While driving at 45-50 mph vehicle hydroplaned and crashed directly into a brick wall. Upon impact, both frontal air bags failed to deploy. Dealer was notified.