2020 Mercedes-Benz A-Class POWER TRAIN,ELECTRICAL SYSTEM

I was driving and I got coolant error on my dashboard. It came and then off. I pulled over and nothing seemed wrong with my engine. I restarted and headed home. The error was still on but the car was driving fine. I was trying to make it home. The car suddenly had all sorts of errors. It told me that my car was undrivable. I had no control over my car going 55 mph on a highway. I was luck to steer the car to the side of the road. Even when I was on the side of the road, I could not put it in park. It kept telling me my car was in danger of rolling away. I had my husband come meet me on the side of the road and he parked behind me so that my car did not roll away. I was on a slight incline on 32. We then waited for a tow truck. During that time, I tried to restart my car - only for it to give me undriveable, blind spot assist inoperative, errors. I could remember all of them. The tow truck guy had no idea what was going on either. My car spent 22 days at the dealership. It took them days to figure out what might be going on. Obviously the PMC module was bad. But why? They think condensation or leak from the AC hose had caused this problem. They found corrosion on the wire harness connector to PCM and on the PMC pins. They replaced the PMC and cleaned the pins. They got the car running - however, a week later, the same issue started happening. Now my battery said is was not charging. We figured it was time to change the battery anyway but it still will not turn on. I just had a full 50k service complete at this dealership in May 2024 There may be further damage to the system that the dealer realized. My car still does not run and I don't feel safe driving it when I can power it up.