Cut and paste this URL to share the unmodified register and value:
https://regviz.com/r/STMicroelectronics/STM32U599/FDCAN1_RAM/FDCAN_ILS#0x0
FDCAN Interrupt Line Select Register
RxFIFO0
RxFIFO1
SMSG
TFERR
MISC
BERR
PERR
https://github.com/cmsis-svd/cmsis-svd-data