HP Spectre motherboard issue

[zim3]

TLDR:

My computer is having charging issues with the USBC port and it needs a new motherboard (we found out through multiple reputable repairpersons and through reading other support posts). My warranty is expired, but I have seen many other expired cases just like mine with the Spectre that HP has helped, despite an expired warranty. I was hoping that they could do the same for me, as the computer costs around $1,500. I was expecting this computer to last me around 4 years, but it is failing at under 2 years. 

The problem:

When my computer gets below 30%, it does not charge until it is fully dead and has sat without charging for around 24 hrs. I do not know why this is, but diagnostic tests have revealed that the battery is in good shape, so it isn't that. After I let it sit for 24 hrs and I plug it back in, it can trickle charge back to 100%. This is extremely frustrating.