I replaced the battery myself last year November, It had been working fine until now....
Last 6 Months, I left my Surface Book 2 on desk and I took my another Surface Pro for to-go. That was why I enabled Battery Limit in the UEFI(/BIOS) settings and limit the maximum charge to 50%.
Yesterday, I disable Battery Limit and let it charge to 100% overnight. But it stuck at 88%. Battery status shows that Battery 1(Tablet part) stuck at 50%.
I've try all that I could think of:
Enable & Disable Battery Limit again
Charge it while completely shutdown
Detach the tablet part and charge it with a Surface Cable alone.
Charge it with USB-C
Charge it while running Linux
Both of the Battery shows healthy in Battery report, not much wear have got.
I suspect it's either the EC on the motherboard or the Power Management chip on the Battery 1 is malfunction, it doesn't disable Battery Limit like Battery 2 does.
It could also be a faulty battery I got But I think you should be aware of this issue.