I recall the last action before I started to have the issue and I now suspect it was my particular scenario of charging the din base battery that might have damaged one or more of the power distribution mosfets. I shall describe the scenario here as a caution for fellow core s3 owners.
firmware installed: uiflow 2.0.1
external device connected: M5Stack GPS/BDS unit connected to port c at the din base.
charger used: wall charger with multiple usb c and a ports. one of the usb c port was used.
sequence of event:
I suspected that in sequence 4 one or more mosfets were overheated and damaged.