Hello DonAcker,
We're sorry to learn about this issue on your device.
In that case, try to force your device to shut down by holding down the power button. This clears the hardware cache on your device. Please also be reminded that Surface Duo already has the recent update (May 27 release) which improves device stability and UI stability. With that being said, we also recommend to Update Surface Duo to keep it running smoothly and securely with all the latest improvements and features.
Let us know how it goes by simply replying on this thread.
StevenK