Do you see a message like "Before making changes to your security info you must complete multifactor authentication."? If so, the likely issue here is per-user MFA, and you can resolve it by resetting the MFA status on your account. Basically, use this link, locate your account, select it and toggle the status to disabled (you can toggle it back if needed).
Some more details can be found in this article, if you are interested in the troubleshooting steps: https://www.michev.info/blog/post/6242/the-strange-case-of-a-login-loop-caused-by-phantom-proofup-requirements