The strange case of my dead msi

2 months ago my MSI GP60 2PF Leopard Pro died unexpectedly. It had been getting hotter (never died because of it though), but it has been that way more or less since I got it (I've had it for 3 years, it was bought second hand from work). I tried the 60 sec remove static trick thing, I checked the charger (works on my old laptop) and cleaned inside but nothing worked. Initially, I assumed that the charging outlet on the laptop was the problem, because no lights would turn on etc, and when I wrote to different repair shops (including MSIs own repair thing), they said they couldn't help because it's too old (it's from some time around 2016-2017, I bought it in 2018). My brother suggested that I should buy a new battery, but I didn't see the point at that time, thinking it was the outlet. A few weeks ago, I randomly tried to connect the charger to the MSI and the blue charging light went on for a while and then the orange/red light blinked saying that the battery couldn't be charged. I assumed my brother might've been right, and bought a new battery for it. I tried the battery today and the blue light turned on for (I assume) as long as it was charging and then turned off. So, the battery seems to be working, the problem is, the computer still won't turn on or give any other sign of life than that the battery could be charged. Any ideas about what I can do?

Thank you!

/Lovisa