2011 dodge charger SE

My 2011 dodge charger SE fully loaded car, only has 34,000 KLM on it. It is a
beautiful car, mint, looks like a brand new car. It ran perfect for 7 years. In
December it died. I got a new battery from a Chrysler dealer in Windsor. I had
to go in there twice because the first time they said nothing was wrong with
the car. The second time they said it needed a new battery, which i
purchased ($500.!!!!!!!!). A few weeks later again the car is dead and won't
start. To make a long story short, I had to bring the charger back to the
dealership like 7 times. They keep saying either nothings wrong or the battery
cables weren't tight enough. I've used up all the CAA service calls, having the
car either jumped or towed in to that dealership, only for them to say come
pick up the car because there's nothing wrong. I asked them to replace that
new battery (2 yr warranty) because perhaps its defectve, but they refuse,
saying nothings wrong with the battery and nothings wrong with the car. Now
when I call there and ask to speak to the Manager of the Manager (because
the local managers are so RUDE. I tell him the whole story of what's been
happening, then he says to me "this conversation is over".
Today I go to leave for work, car is DEAD again. This is like the 8th time. I
called the manager of the manager (top guy) at the Chrysler dealership and
told him over the phone what is happening. He told me "this conversation is
over" and hung up on me. I brought the car to another garage and the
mechanic said the battery wasn't installed right, and he tightened everything
and the car is fine now. NOPE. Two weeks later the car dies again. WTF!!
What am I supposed to do now????????????? Chrysler dealer won't stand
behind the battery warranty and wont replace it because they say nothing is
wrong with the battery. No one knows what wrong. I don't know what to do. I
am so frustrated that I'm getting chest pain.