Hello sorry to hear you are experiencing issues logging in. This happens from time to time. Please follow these instructions to refresh your Github SSO:
Login to Netlify using the email address and password only.
If you do not have a password configured, you can add one by using the password reset form: Netlify App
Once logged into Netlify with the email address and password, then change the GitHub account associated with this email address here: Netlify App
Log out of Netlify.
Once this is done, you should be able to log into Netlify using GitHub or the email address. Both methods of login should work now. If they do not or if there are any other questions, please let us know.