Brake Master Cylinder problems of the 2013 Chevrolet Volt

I bought a 2013 Volt 2 weeks ago. While at the cvs drive through today the car started to beep warning lights when off, brake pedal went to the floor and the car started moving forward. The brakes completely stopped working, no pumping or anything. I made it into a parking space to await for a tow truck and turned the vehicle off. When I turned the vehicle on the error messages were gone and the brake pedal felt solid again. I started to move the car and the errors came back and brakes failed again. The experience was overall kinda scary. I towed it to the dealer. 2 days later I called the dealer and they informed me that the master cylinder had failed and must be replaced.