Hi all!
I have a 2012 Captiva and it wont start. In August 2021 my car shut off all the way and the key was stuck in the ignition. It was towed to a Napa mechanic and I was told the battery and alternator was bad and had them replaced. Then in April 2022 it did the same thing again. I took it then to a chevy dealership and they told me my fuel injector needed to be replaced and that was done. And then, again, in August 2022 it died again. All the times it died, it did the same things. There are random warning lights that appear on the dash and the car turns off, but never back on. In Sept I took it back to Napa because the dealership weren't being any form of helpful (obviously). Napa told me the starter needed to replaced, had it replaced, and after one trip to and from work (approx. 10 miles) it cut off and now it won't turn back on. It has been sitting since. This time when it cut off, the radio cut off and there's no power running through it. I am 100% sure the battery needs to be replaced again. I'm thinking the issue is a wiring issue with the cables to and from the battery. I found a video on YouTube where you can jiggle a cable and the car turns on, which worked. And that's what led me to think it's a wiring issue....any advise??? Please help!!!
P.S. i attached the video from YouTube, in case it might help with an idea where it is.

https://youtu.be/EHfbbQe-iqw

Thank you!!!!