Brakes Failed problems of the 2017 GMC Sierra 1500

Tl the contact owns a 2017 GMC Sierra 1500. While driving approximately 20 mph, the brake pedal was depressed and traveled to the floorboard. The brakes failed to adequately slow down the vehicle. Prior to the failure, the vehicle was taken to mastria Buick GMC (1525 new state hwy, raynham, MA 02767, (508) 880-7000) to be repaired per NHTSA campaign number: 19v645000 (service brakes, hydraulic). The contact stated that the failure recurred twice after the repair. The manufacturer was not notified of the failures. The approximate failure mileage was 40,000.

Total brake failure. The pedal became hard as a rock with no advance warning. I received a notice (n182202780) from gm stating that I might experience increased brake pedal effort. It went on to say how this notice "is not a reacall" and that brakes still meets "all federal motor vehicle safety standards for brake performance" I'm writing to bring attention to the fact that my truck experienced no symptoms of a problem until the pedal had maybe 10% assist. No check engine light or notice from the drivers info center. I applied the brake, shifted into drive, accelerated then applied the brake to stop and maybe had 10% braking ability. The notice also went on to say that "failure to follow recommended oil change intervals could contribute to this condition". The truck has 32000 miles on it, I've owned it since new, I have always changes oil with 20% life left in it. This is about 2000 mile sooner than the manufacturer recommends. This is a very serious condition that gm has recognized in there letter, but in my opinion, are not taking it serious enough. Unless I'm a "one off" case, this will very likely get people hurt and property damage if not addressed very soon. Please look into this, thank you.