Hi! My ASUS X455L has been with me for 3 years now and just before 2020 ended, my battery started acting up. At first it failed to show that it was charging, so we got that checked and fixed but then after a while it started to drain like most batteries but it fails to increase. I've been through a total of 4 battery purchases and returns and 3 check-ups. I just don't know what's wrong with it anymore. It's not the charger or the battery as I made sure to buy original ones. Software-wise, I'm unsure if that would be smart.. my laptop is updated and I don't delete program files or logs. Is it time for my laptop to be "charger dependent"?
It appears the charging circuitry inside the laptop isn't working correctly. This would include any cabling to the battery. Not something you are likely able to fix yourself. It would require a knowledgeable repair tech. If you've been taking it to a repair shop, you need to go elsewhere.
I don't know if ASUS has diagnostic software available, but see if they have a battery diagnostic you can run.