Side/window Air Bag problems of the 2015 Lexus IS250

The latch covering driver side air bag falls off repeatedly, leading to concern there is a problem in that area that could affect the air bag itself. Car has been to the dealer at least a half-dozen times for repair without actually getting a lasting repair. Filed a formal complaint with Lexus three weeks ago, they promised to get back within 10 business days, they did not, and when I phoned today, they continue to stall. No fix. No resolution. The date noted below, oct. 1, is merely one of the dates of the issue, which is ongoing and has been ongoing all year.