Customize Your Login Process with My Domain

When I try to launch my trailhead developer edition, It fails with below error

"This site can’t be reached
curious-badger-vv2jvj-dev-ed.my.salesforce.com’s server IP address could not be found."

I am guessing because of the new domain created. 

But the trailhead is still trying to connect the old domain how to make it redirect it to new domain.
Please help me complete this challenge