Find the hotspot inside interactive book causes sudden stoppage after first screen

Disclaimer : I am a very beginner in this technology and new to this site. Apologies in advance if I am submitting this report on the wrong page/ with wrong tags.

1.Problem: I created an interactive book with 3 pages. each page has a  picture followed by 2 "find the hotspot contents. When viewed it is howing a weird behavior. the intro page is first shown. then user clicks the "read" button and first page is then shown. however , when user clicks the next page arrow, the page does not change. their seems to be no change on screen and it feels as if the page is somehow stuck

What's more weird is when i refresh this page the intro page is again shown. when user clicks the "read" button, this time the first page after intro (the one which was shown previously and had got stuck) does not show at all and 2nd page opens directly.

Why is this happening? and how can it be rectified? I want to show 3-5 slides having an image followed by 2 find the hotspots game. Which other content type can be used to create such thing?

2. Steps to reproduce:

a. Create a new Content. Select its type as Interactive Book(alpha)

b. enable the book cover check all the boxes in behavior settingd

c. add a picture and introductory text  to intro page

d. next create 3 pages having one big picture followed by 2 find the hotspots games

3. Example: following link directs to the content i created and the one which is showing the bug : https://h5p.org/node/470804/ 

4. Platform and version number: Mobile, Web (I used h5p.org's account to create the  content and on saving it, i was able to view it from my h5p account. the bug was happenning on the browsers of both mobile and desktop, when 'viewed')

5. Mobile or Desktop : both

6. Browser: Chrome(Android), Chrome(MAC), Chrome(Windows), Opera(Windows)

7. URL: https://h5p.org/node/470804/

8. Any browser console errors: No idea

9. Any PHP errors:  No idea

10. any recent changes to the environment (new plugins/modules, updates, configuration changes etc.): no environment istalled