2024 Prius Prime XSE Premium - 2 dead 12v batteries at 7000 in SoCal

Yet another dead battery story. This is an interesting one. So I bought a used 2024 Prius Prime XSE Premium with 6000 miles on it in March from a Toyota dealer. The dealer says they replaced the battery before selling it to me. The car ran fine until late April, the battery died. I watched the wrong youtube video and crawled into the trunk to pop open a hatch to release the trunk. Why the hell did they make it so hard to open a trunk on a dead battery??! I later saw another youtube video that teaches you to jump the car from the fuse box. Anyway, I got it over Longo Toyota. They verified the battery is dead and replaced it with a new one under warranty. I asked them to make sure all software updates are in. They said "yes they are". Today, I get a low battery warning after I get to work. I've only went 500 miles on this new battery. I'm pretty sure the car is going to be dead by the time I get out. What the hell.

My question: If the dealer says all software is up-to-date. What are my options? I cannot keep taking this to the dealer. I need a reliable car. I saw this on TikTok, wondering if any tried hooking up a Ancel BS200 Supercapacitor? Its like a permanent jumper you latch onto the battery to take off the load. Kind of like the old school car audio farad caps in the early 2000s.