Cut and paste this URL to share the unmodified register and value:
https://regviz.com/r/STMicroelectronics/STM32H7x5_CM7/EXTI/D3PMR3#0x0
EXTI D3 pending mask register
D3 Pending Mask on Event input x+64
https://github.com/cmsis-svd/cmsis-svd-data