This is an issue that does happen occasionally. If you are seeing this on the end of your url   /2factauth/qr please clear your cookies and browser history before trying to access it again. Try and type in the link to the URL if you can after clearing your browser history, and avoid using any saved links or passwords.

If you still have problems logging in after this then please try to use an incognito window in your browser. You can find out how to do this here,Press%20%E2%8C%98%20%2B%20Shift%20%2B%20n.