Timed Quiz - Not recording all answers if time runs out

Hi Wendy, 

Thank you for your response.

I had a look at the tutorial you sent.

This is exactly how i set my course up, so very confused that it doesn't work for me. Any unanswered questions have not been taken into account of the final score. My course is set up with 30 questions, i have only answered 18 of them before the timer runs out it gives my over passing rate from the 18 questions and it shows i passed, where as it should show i've failed as the pass rate is set up at 80%. The overall score should be marked out of 300 points with a passing rate of 240 points.

This occurs in preview mode, as well as when it is published online.

Please see screenshot attached. 

Thanks again, Amy