Cut and paste this URL to share the unmodified register and value:
https://regviz.com/r/Silicon Labs/Series1/EFR32MG12P/EFR32MG12P231F1024GM68/GPIO/PC_PINLOCKN#0x0
Port Unlocked Pins Register
Unlocked Pins
https://github.com/cmsis-svd/cmsis-svd-data