The contact owns a 2021 Chevrolet Tah. The contact stated while driving at an undisclosed speed, the brake pedal was depressed; however, the brakes failed to function as intended. In addition, the contact noticed a grinding sound and several unknown warning lights illuminated. The vehicle was taken to the dealer where it was diagnosed with brake master cylinder failure. The contact was informed that the brake master cylinder needed to be replaced. The vehicle was not repaired. The contact stated that the brake master cylinder had been replaced two times since October 2024 and needed to be replaced a third time. The manufacturer was made aware of the failure and a case was filed. The contact was provided a monetary discount towards the cost of the repair. The failure mileage was approximately 35,000.