Using the incorrect login details.
This type of issues occur due to server error.
Error in your internet connection.
Error in your web browser
Logging in may be hampered by any firewall or third-party software.
Credentials that have been forgotten, etc.
Read more here:- https://www.datarecovo.com/how-to-fix-sbcglobal-email-login-issues/
If you have the Delta app, you can often find a live chat option or a direct phone number for customer service. It is a right to use direct phone. I am working with PowerPoint design agency uk to deliver quality ppt design presentations.