Try a different browser or reset the browser to clear cookies and cache and unload any add-ons or extensions that may be blocking essential cookies. A full browser reset will normally get you back to normal. A few seconds of the spinning circle should be all that you see unless there's a mailbox connection issue.
After a browser reset the recommended sign in is here:
Select here: Sign in to TalkTalk Mail
Enter your full TalkTalk Mail email address, select Continue and enter the password, select Sign in.
