Cut and paste this URL to share the unmodified register and value:
https://regviz.com/r/STMicroelectronics/STM32U599/FDCAN1_RAM/FDCAN_ILE#0x0
FDCAN Interrupt Line Enable Register
Enable Interrupt Line 0
Enable Interrupt Line 1
https://github.com/cmsis-svd/cmsis-svd-data