Can anyone help me?

I have created a course in Storyline 360 and my graded quiz at the end works perfectly when I preview but when I publish for review the quiz doesnt work - learners cant select the radio buttons and cant move through the quiz.

I have made a new scene and added the questions from scratch (not copied) but keep getting the same result.

Does anyone have any idea?? Ready to throw it out the window.

Thanks,