2021 HONDA ODYSSEY Vehicle Speed Control Problems

After the PGM-FI update was put into our car, the engine cuts out entirely while at stop lights and will not wake back up. The Honda dealership is saying that there is nothing they can do.

Once the cruise control is set, it consistently drops below the set speed and surges back up or over the set speed. Set on 62, it drops to 59 or 60, then surges back up to 62 or 63. This happens on perfectly flat roads with no traffic in front or beside the car. The dealership tried to tell me that the camera for the adaptive cruise might be seeing things in its peripheral vision area, but there is nothing there, the shoulder of the road is wide and free of obstacles. I've owned many other brands of vehicle, and never had this trouble with the cruise control on any of them. This is also a safety issue because sometimes it just randomly slows down or speeds up when there are cars behind you or beside you.

I have a 2021 modely Honda Odyssey Elite (purchased in November 2020). This car has 14,000 miles on it as of July 29, 2022. When accelerating from a complete stop or accelerating after slowing down, upon depressing the accelerator pedal the car simply refuses to accelerate for a second or two and simply coasts due to momentum and then after a while accelerates hard causing a sudden jerky take off. This might not seem like a big issue on its face, but that delay has almost caused me to get hit by the oncoming traffic especially when making a right turn or when changing lanes. I have 3 small kids (one of them a baby, and a five year old) and this is a precarious situation to be in. Also, this happens intermittent in all weather conditions (be it cold or warm or hot doesn't matter) and we don't know...