STM32L0x WWDG in Stop Mode -> Problem

Hello

I'm using the STM32 Window Watchdog (WWDG) to make sure my firmware behaves, as it should. My problem is, as soon as the MCU wakes up from STOP-Mode, the WWDG makes an immediate reset. As i saw in the reference manual, the WWDG should be stopped in STOP-Mode and continue to work as soon as the system wakes up.

Does anyone else had the same problem or an idea?

thanks for your help!