Cut and paste this URL to share the unmodified register and value:
https://regviz.com/r/STMicroelectronics/STM32L4x1/FLASH/ECCR#0x0
Flash ECC register
ECC fail address
ECC fail bank
System Flash ECC fail
ECC correction interrupt enable
ECC correction
ECC detection
https://github.com/cmsis-svd/cmsis-svd-data