A:AnswerThere could be some drivers that need to be updated. You can check for driver updates here:
http://support.lenovo.com/us/en/products/Laptops-and-netbooks/ThinkPad-X-Series-laptops/ThinkPad-X1-Yoga-Type-20FQ-20FR/20FQ/001VUS?linkTrack=Homepage%253ABody_Search%2BProducts&beta=false
If the driver update doesn't correct the issue, here is an article about "wake from sleep" issues with the ThinkPad X1 Yoga an the steps to take next:
https://forums.lenovo.com/t5/ThinkPad-S-Series-ThinkPad-Yoga/Thinkpad-Yoga-not-waking-up-after-sleep/td-p/1348909/page/3