Cut and paste this URL to share the unmodified register and value:
https://regviz.com/r/STMicroelectronics/STM32W108/CLK/CLK_HSECR2#0x0
HSE Clock (24MHz) control register 2
OSCHF/XTAL is selected
MHz crystal oscillator is main clock
https://github.com/cmsis-svd/cmsis-svd-data