Cut and paste this URL to share the unmodified register and value:
https://regviz.com/r/stm32/stm32l5/STM32L552/GTZC_MPCBB1/MPCBB1_CR#0x0
MPCBB control register
LCK
INVSECSTATE
SRWILADIS
https://github.com/modm-io/cmsis-svd-stm32