Sorry to hear about the issues you've been experiencing with your car. It's great that you have a warranty and can send it for repairs. As for the rear sunshade, I haven't personally heard of any issues with it, but it's always a good idea to have it checked out when you're taking your car in. While waiting for your car to be fixed, consider looking into custom-made sun shades from
https://snapshades.com/. They offer high-quality shades that are designed to fit your car's windows perfectly, and they're great for protecting your car's interior from the sun's harmful rays.