Quick fix for my quiz website

I run a quiz app online, and currently there is a small bug. If you run down the timer, the test will not mark itself. It only marks when you manually click end exam. Our aim is to make the website mark itself once the timer runs down.

Sample Quiz on my website:
https://braindocacademytests.com/#!/exam/17da5b0245f3312837b6ff4ab7135a9e/123