Force lock screen?

[k1ngr4t]

So I use a S-View case for my Note 3 and for whatever reason the screen doesn't always lock when I close it. Sometimes it will, but other times I'll flip it open and it'll be on the screen I last left it, even if it's been over a few minutes. I want the lock screen to appear each time for multiple reasons but can't figure out how...

Any ideas?