Thanks for support.
I have created a quiz as follows
Page 1 Text/HTML section
Page 2 quiz-1
Page 3 quiz-2
Page 4 quiz-3
Page 5 quiz-4
Page 6 quiz-5
Page 7 Text/HTML section
On page quiz-4, the submit button is displayed and
I could not access to quiz-5.
After removing the first and last Text/HTML section
quiz-5 is also displayed.
