Citi Trusted Identity Already In Use
This happened when I had a previous user ID using Citibank app. You must login to the old account and remove the two-step authentication and access to trusted ID.
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Community members who reach Level 5 in the community can create User Tips to share knowledge about Apple products. Check out this User Tip created by Lawrence Finch: When to charge your iPhone or iPad
Community members who reach Level 5 in the community can create User Tips to share knowledge about Apple products. Check out this User Tip created by Lawrence Finch: When to charge your iPhone or iPad
This happened when I had a previous user ID using Citibank app. You must login to the old account and remove the two-step authentication and access to trusted ID.
How to contact a third-party app developer
If you encounter any challenges with third-party applications, the best course of action is to directly contact the app developer for further assistance. Here's a brief guide on how to do it:
By reaching out to the app developer, you increase your chances of receiving accurate and personalized support for the challenges you're experiencing. To contact an App developer --> How to contact an app developer - Apple Support

How to contact a third-party app developer
If you encounter any challenges with third-party applications, the best course of action is to directly contact the app developer for further assistance. Here's a brief guide on how to do it:
By reaching out to the app developer, you increase your chances of receiving accurate and personalized support for the challenges you're experiencing. To contact an App developer --> How to contact an app developer - Apple Support

If you're already using two-factor authentication with your Apple ID, you can't turn it off. If you updated to two-factor authentication inadvertently, you can turn it off within two weeks of enrolment. If you do, your account is less secure and you can't use features that require a higher level of security.
This happened when I had a previous user ID using Citibank app. You must login to the old account and remove the two-step authentication and access to trusted ID.
this is actually the correct answer. I just responded to a previous question and couldn’t reply so I created a new message. Oops.
Citi Trusted Identity Already In Use