Cut and paste this URL to share the unmodified register and value:
https://regviz.com/r/Silicon Labs/Series1/EFR32FG14P/EFR32FG14P233F128GM48/CMU/DPLLCTRL1#0x0
DPLL Control Register
Factor M
Factor N
https://github.com/cmsis-svd/cmsis-svd-data