In order to view the repository you need to be signed into GitHub with the same username you entered into your settings on this website.
If you haven’t already done this, move your mouse over your name in the top right corner of this page, select Personal, on the left select Connected Accounts, then enter your username into the GitHub field (it is case sensitive), then click Save at the bottom of the page. You should receive an email confirming the change, make sure you are signed into GitHub, then try clicking the link again, it should work.