Cut and paste this URL to share the unmodified register and value:
https://regviz.com/r/Atmel/ATSAM4S4B/PMC/CKGR_PLLBR#0x0
PLLB Register
PLLB Front-End Divider
PLLB Counter
PLLB Multiplier
https://github.com/cmsis-svd/cmsis-svd-data