2020 GMC Terrain

My Terrain has a light that has been coming on for a couple months. Service Brake Assist. I took it to the dealer after my brakes locked up and about $800 after getting it fixed the light continues to come on. The forward collision light comes on every time I start the car. More the check engine light came on and says engine electrical system. What the heck is going on? I love this car and take very good care of it but I feel like the $800 that I just spent was a waste. I fear that I will get in a wreck like when the brakes totally locked up and I couldn't press on them.

This GMC I just purchased in October 22 2022 and have been complaining since December 9,2022 the vehicle emergency braking will activate when I'm driving down the interstate or local roads I could be doing 70 and brakes will just lock up throwing me and my son forward , this has happened 4x , Gas Pedal when taking off at red light or pulling out the vehicle is hesitant and will not go this has happened on 3 different occasions. I called roadside on star they said there is a problem with the on star saftey feature will not work properly this was towed 2x to different shops, Also while driving this vehicle it will just ingage itself in park while driving called on star they did diagnostic there was all kinds of Coded for Transmission and Engine as well as Emissions this vehicle is a safety hazard.. And I have tried to take back to dealership where I purchased they keep making excuses to not see this CPO with lifetime Warranty and still under warranty from GMC vechle Mileage was at 29k when problems stared vehicle only has 31k I can't drive this vehicle due to my son's and myself along with others saftey this is ridiculous and also GMC just informed me the Vin # they have for my vehicle and whats on it are two different numbers! Yet nothing is being done I'm paying for a vehicle that I can't drive I have proof GMC knows about the fraud from dealership but GMC says its a sales thing This vehicle has been flooded two mechanics have confirmed and GMC is aware so why not do something I don't know exactly the history and GMC doesn't either please someone contact me GMC this is crazy and you know it's a safety issue with this 2020 GMC Terrain you even said so

Not long after I bought my 2020 GMC Terrain my adaptive cruise started disengaging. There are never any warning lights, except the noise and vibration of the seat before it shuts off then tells you it's disengaging. I didn't think anything of it until it's became a regular occurrence in the last month or two. I tell my dealership about it and they drive it but it never disengages on them, so they say nothing is wrong with my vehicle. I have a picture of the "adaptive cruise disengaging" and video of where I can't reset it until after about 15 or so minutes or letting my car set for a while or turning off the engine then it works again. I also have noticed that my auto start/stop hasn't been turning on & off anymore.

On fairly level ground, reduce speed hill descent control msg has activated (12 mile and maxwell area 2x, Rochester Hills Kohls parking lot exit) and once entering river bend dr. vehicle has also has had activated brakes on oak hill street in rochester. the vehicle has less than 4100 miles. very concerning about activated brakes.