Locked out of Codex because of an old phone number

Welcome to the community!

OpenAI’s help article says phone numbers associated with an account can’t currently be changed or updated self-serve. That applies to both ChatGPT and the OpenAI API:

https://help.openai.com/en/articles/9135134-how-to-change-the-phone-number-associated-with-your-account

Because you no longer have access to the old number and Codex access is blocked, I’d recommend that you open a support case through the Help.

Include the account email, workspace/org details if relevant and explain that you no longer have access to the old phone number being requested.