I approached the intersection slowly and stopped completely to turn right. There were a couple of vehicles in front of mine. I pushed the 'Auto Hold' button while waiting on the Red light. A second later, I felt the car moving on its own and stepped on the brakes. The car did not stop and went forward and crashed into the vehicle in front of me. My vehicle did not stop after the initial collision and accelerated more on its own and went forward. I pushed the 'Park' button to stop the car but it did not work and the vehicle kept moving forward fast and hit another car. It still kept moving fast until it hit other things. The car stopped after it went through a wire fence and hit a tree. The brake did not work at all. The car never stopped once it started moving on its own. Forward collision warning never came when it was approaching the first vehicle in front of mine on its own. The 'check engine' light was on for 3 days and disappeared on its own about 1 month prior to the accident. I tried to take it to the service center immediately but the earliest appointment I could get was in June. The service adviser at Hyundai service said there was nothing that they can do since the warning light was not on when we asked for a service check on 6/11/22.