2005 Hyundai Santa FE seat belts problems

Tl* the contact owns a 2005 hyundai santa fe. When the contact entered the parked vehicle, the driver's side door air bag deployed without impact or warning. The contact sustained injuries to the left ribs that required medical attention. The vehicle was not repaired. The manufacturer was notified of the failure. The failure mileage was 120,697.

I purchased the vehicle used march 2014. The back passenger seat belt from the beginning is finicky. Sometimes it would click and lock and sometimes it never engages. Because of this we decided to just not use that seat. We thought maybe it just needed replaced. Now, yesterday, the middle seat belt came undone while my child was strapped into his car seat. I was going from a stop and turning into the grocery store. My son's seat fell on it's side. I don't know how long it had actually been undone at that point.