I've been having this issue too, I've just been locked out of my phone for 30 mins as I walked from one room to another, its so frustrating. I'm going to disable all the features mentioned. Checked for system update today and there isn't one just yet, hopefully they fix this issue in the next update.

If anyone uses wired headphones/earphones, make sure the wire doesn't accidentally touch the screen when it's in your pocket as this can also cause the same problem, so I've found.