Before going through these steps, please ensure you’ve tried to log on using the ‘Enter your existing site address’ login screen. Then, you will be asked for your site address, username, and password. You can find instructions on how to log in with your self-hosted site here.
If you’re running a self-hosted installation of the WordPress.org software, connection issues are typically caused by one of two things:
Please follow those links for more help troubleshooting those issues.