AT&T Messages Backup & Sync login redirecting to main sign-in page
When attempting to login to messages.att.net for a phone line, I am redirected to the regular myatt homepage login. However, on the same computer another user can login and view their messages perfectly fine. I have followed the steps outlined in the tutorial and have read through responses on the forum already, so please do not suggest the standard. When viewing the console, I see the following error for the account with the redirect problem:
Failed to load https://myattlog.att.com/....[removed]. The 'Access-Control-Allow-Origin' header contains multiple values 'https://www.att.com, *', but only one is allowed. Origin 'https://www.att.com' is therefore not allowed access.
Please advise. Thank you.