Kinko_1
Hello,
There is no shop domain name added to your account, can you check it by going to the subdomains section of your hosting account? If the subdomain name is not listed there you can add it again and it will start working.
As for why the blog subdomain redirects to the 404 page, it might be because there is no index page on the blog subdomain folder. please create a new index file and check it and let me know.