Cut and paste this URL to share the unmodified register and value:
https://regviz.com/r/stm32/stm32wb0/STM32WB07/I2C2/I2C2_RXDR#0x0
I2C2_RXDR register
Eight bit (8-bit) receive data Data byte received from the I2C bus.
https://github.com/modm-io/cmsis-svd-stm32