Where is the hang-up button?

I noticed this the other day, but figured it was just a fluke thing......I've now made about 10 calls on my OnePlus 2 and when I'm finished with my call, I don't have a hang-up button! I have to hit the home button, then swipe down and choose "Hang Up" from the little window there. Doing this is a quite a chore because the sensors detect when the phone is by your face and shuts off the screen, so when I try to touch my screen it will shut off the screen. I eventually get it, but it sometimes takes about 30-45 seconds to end my call doing it this way.

Am I missing something? Is one of the softkeys (on the phone) now the hang up button?