I just got my watch series 3 today and I was trying to get it set up to unlock my mac. I have a MacBook air model 6.1 which the website says is mid 2013 so it should be the earliest that can do this. When I try to set it up in settings it says "Unlocking your Mac not supported with your apple watch. Update your Mac's software to allow your Apple Watch to unlock your Mac." All my software is up to date. Any ideas?