Can't access WP admin panel installed on subdomain
I created the subdomain using this guide. https://www.godaddy.com/help/manage-my-subdomains-web-and-classic-hosting-4652
Then I installed Wordpress on the subdomain using this guide. https://www.godaddy.com/help/how-do-i-install-an-application-to-a-subdomain-or-non-primary-domain-17...
The installation seems to be successful. I can go to the subdomain and I see a Wordpress installation. The theme seems to be messed up. However when I try to login by going to the provided URL or going to the Manage Applications page and clicking Login, I get a 404 error.
How can I fix this?