start writing paper letters instead of e-mails. Usually companies take those more seriously. Paper letters means "ok he is really talking business now".
That's were the "good friends" part comes in, a dinner invitation every once in a while works for me, but I'm sure you can find a lawyer that charges a small amount for the same thing.
This “summary” is so wrong. You left out half of the article describing problems with the camera and on-board computer leaving every modern feature of the car useless, which is a known problem affecting a huge number of customers, and which they promise to maybe fix in three months. The only problem you mentioned in your summary, the mysterious battery loss, isn’t even officially acknowledged let alone promised a fix.
And what’s the point of a “summary” when TFA opened with a very good two paragraph summary of the situation? Can’t even tell if it’s gaslighting to make light of the problems, or some stupid AI summary service running amok.
* they sold him a broken car in December, that keeps losing battery 8% per day even when standing out doing nothing
* they told him they could repair it, at the end of February, because of high demand for the part
* he cannot now go to holiday peacefully and has to charge it nonstop
* he doesn't consider the car safe to drive it all the way to the service center, because it basically doesn't work
* the customer support is ignoring him
Sounds like a nightmare alright. If I was him I would start getting lawyers/customer rights groups involved.