9650 battery runs of battery suddenly

Hi,

I have my 9650 since 2017. Recently, I've noticed the battery will drop suddenly. Like from 65% to 10. Is this bc the battery is dying or something else?

Battery life is not as good as before (not surprisingly). Battery drain is pretty fast. At 100%, window 10 says less than two hours.

I'm using throttlestop to undervolt and turned off msi afterburner.

Thanks.