Bootloader issue for new development hardware for FMU-V6x

Dear all,
I’m trying build a hardware prototype under Pixhawk FMUv6x standard, and I feel the bootlander was diffence with before. I had compiled the bin file of bootlander from FMUv6x source code, and load into STM32H7, but it’s not work on my hardware prototype of STM32H743II + FM25V02(configure under source code).
Any one has any idea for this issue?
Thanks for your feedback.