Cut and paste this URL to share the unmodified register and value:
https://regviz.com/r/stm32/stm32wl/STM32WL5x_CM0P/PKA/CLRFR#0x0
clear flag register
Clear PKA End of Operation flag
Clear PKA RAM error flag
Clear Address error flag
https://github.com/modm-io/cmsis-svd-stm32