Chosen Solution
Well, the good news is you changing logic is working! Your battery is just bad. Given its age it was likely bad from the start. iFixit offers a year warranty do you still have your paperwork to see if you can get a free replacement. I would try that first contacting iFixit Customer Support Just like tomatoes you can get a bad one in the bag.
If you download Coconut Battery you can find out more about the health of the battery: https://www.coconut-flavour.com/coconutb… You can also try resetting the power management, Google for “reset pmu” to find how.
