Cut and paste this URL to share the unmodified register and value:
https://regviz.com/r/Fujitsu/MB9BF52xT/FLASH_IF/FSTR1#0x0
Flash Status Register 1
Flash Rdy
Flash Hang flag
Flash Chip Erase Status
Flash Erase Suspend Status
Flash Sector Erase Status
Flash Program Status
https://github.com/cmsis-svd/cmsis-svd-data