Cut and paste this URL to share the unmodified register and value:
https://regviz.com/r/STMicroelectronics/STM32G473xx/FDCAN1/RXF1S#0x0
FDCAN Rx FIFO 1 Status Register
F1FL
F1GI
F1PI
F1F
RF1L
https://github.com/cmsis-svd/cmsis-svd-data