A Link on Badgey.com's footer can not be reached

[Kerin]

Describe the bug

In our other projects section of the footer, there is a link for Yaydoc project. However, when I clicked on the link, it displays that this site cannot be reached.

To Reproduce
Steps to reproduce the behaviour:

1. Go to footer of 'Badgey's website'
2. Click on 'Yaydoc'
3. Open the tab.
4. See error displayed: This site can’t be reached. Check if there is a typo in dev.yaydoc.org.

Expected behaviour

The website of Yeydoc should be displayed.

Screenshots

Desktop (please complete the following information):

• OS: Windows
• Browser : Chrome
• Version : 87.0.4280.66 (Official Build) (64-bit)

Additional context

All the links of other projects for working well except this.