Cut and paste this URL to share the unmodified register and value:
https://regviz.com/r/stm32/stm32h7/STM32H745_CM4/SYSCFG/UR5#0x0
SYSCFG user register 5
Mass erase secured area disabled for bank 1
Write protection for flash bank 1
https://github.com/modm-io/cmsis-svd-stm32