NHTSA Complaint #11572183 — 2019 HYUNDAI SANTA FE

There is a system in the car that starts and stops engine, supposedly only at lights to save on fuel. Mine has stopped in the middle of a highway on my way up to Tahoe. Luckily I had just left light and only driven enough to reach the speed of about 10 miles per hour so the cars behind me were able to stop and not hit me. I had to completely turn the car off, put in park and restart car to get it to operate. It has stalled out like a stick shift would if not handled properly, but it is an automatic transmission, on numerous times. Sometimes this will cause the vehicle to completely shut down and sometime it will sputter for a few minutes and then slowly pick speed up and stop. The IGS button to turn this feature on and off when you get into the vehicle will sometimes stay off (not supposed to) and sometimes turn back off as it is supposed to each time the vehicle is turned on or off. It doesn't register as a recall, but I have done my research and saw that at one point you guys had done an investigation into this exact problem with my car. It doesn't show up on diagnostic and it doesnt do this every time I drive. So I have no way to show mechanics the isues. But this puts my life and anyone in my cars lives at risk. Not to mention any cars behind me if this happens on the highway again. I dont know what to do :( Can you please help me?