NHTSA Complaint #11459820 — 2020 LEXUS ES350

I always use cruise control whenever i drive because this would always makes me put on a safety automatic brake whenever i get close to the car next to me. But it seems like my automatic emergency brake is defective which Lexus Dealership denies on the inspection when i complain. A lot of times the automatic emergency brake does not work when i use it even when im backing up it suppose to stop but a lot of times im almost at thr brink of hitting something so i have to manually brake. I also texted this to my Lexus Assistant Manager in Lexus Glendale California branch and had it inspected by them but they’ve sit my car in the dealership and at the end of the day told me that its normal. Is it normal to hit a car next to you when youre expecting your car to stop automatically and it does not stop? Why do i have this feature and it doesnt work? I hope you can help me becaus ethis car is very expensive and yet it does not guarantee safety!