It appears that the weblink UDL Guidelines - Version 2.0: Examples and Resources is not working correctly. Unfortunately, this is not something that I can fix within the classroom.
If you conduct a search for the UDL Guidelines, you will be brought to the following website: http://www.cast.org/news/2018/new-udl-guidelines-website-release
From this site, you can click on the UDL Guidelines link to the site needed.
Sample Solution