I can't embed a DRIVE video in the knowled base

Dear UserEcho team,

I have been trying to embed the next code (it's private video, you will not be able to see it):



To the next Knowledge Base: 
http://inboundcycle.userecho.com/topic/435583-crea...

Once I copy it into the edit mode everything goes well, once I save the video desapears.

Thank you!