When you switched it off did you have to take the mains plug out and then replaced it (like a cold bootup)?
These devices do seem temperemental and ours freezes sometimes but an unplug (or long wait) usually works.
Surface Pro 5 News - release date, UK price, features, specs
Gear VR vs. Daydream: Which delivers the best VR experience?
Best Mac antivirus 2017
Synology invites you to visit them at Insomnia on 26th – 29th August. Book your tickets now and visit Synology.