keyboard disable suddenly

Hello,

I purchased my MacBook Pro few days ago, it works perfect and I liked it actually, except that there is a problem that is really annoying me; and that is the keyboard disable suddenly without I do any thing, at first I thought that I pressed a wrong key or some thing like that and I restarted the Mac and it worked, but after that the same thing happened so many times and every time I had to restart the Mac.

If anyone have an idea why that is happening please help me. I hope that will be fast

My regards,,,

My MacBook Pro information:

MacBook Pro 15-inch (2015 edition)

Hard Disk: 512 GB SSD

OS: OS X Yosemite (version 10.10.5)