fully charged psp go seem to lose power in 2 days without using

hi, i bought pre-owned psp go which was on some earlier generation of cfw (not infinity). i recently started playing with it and realised the psp go will not turn on unless i plug in power supply and let it charge, even though i fully charged it 2-3 days before and not playing it at all.

it charges fine and turns on, and im asked to set time and date every time.

i have since updated the firmware to latest and applied infinity, still has the battery drain issue.

i then ordered a replacement battery and tried that, the battery still drains within couple of days after i manually turned it off.

could this be an hardware issue like logic board constantly discharging the battery?

some google search relate the time/date reset to issue with flash 0 or flash 1 partition, and i can’t seem to find any update to date info on how to reformat those partition without risking brick the psp go.