After (lines and polygon) chapter the web page is not available(staging.mon.school) website

[arjun-v1]

Describe the bug
A clear and concise description of what the bug is.
In (staging.mon.school ) website after lines and polygon chapter the web page is showing "there was an error building this page"
To Reproduce
Steps to reproduce the behavior:

1. Go to '..staging.mon.school.' website
2. Click on '...drawing shapes.' chapter
3. Scroll down to '...adding colours.'
4. See error
5. showing error that there was a problem building this page

Expected behavior
A clear and concise description of what you expected to happen.
I expect to fix this problem

Screenshots
If applicable, add screenshots to help explain your problem.

Desktop (please complete the following information):

• OS: [e.g. iOS]
• Browser [e.g. chrome, safari]
• Version [e.g. 22]

Smartphone (please complete the following information):

• Device: [e.g. iPhone6]
• OS: [e.g. iOS8.1]
• Browser [e.g. stock browser, safari]
• Version [e.g. 22]

Additional context
Add any other context about the problem here.

[anandology]

Fixed now and the https://mon.school/ is now live with this version.