Cut and paste this URL to share the unmodified register and value:
https://regviz.com/r/stm32/stm32u5/STM32U535/TAMP/SECCFGR#0x0
TAMP secure mode register
BKPRWSEC
CNT1SEC
BKPWSEC
BHKLOCK
TAMPSEC
https://github.com/modm-io/cmsis-svd-stm32