Hi @QuestionGuy
Good day! Welcome to Q&A forum.
I understand you'd like to remove an old "live ID" (which is now known as a personal Microsoft Account) from the "Accounts and orgs" section in your Microsoft Teams. In this case, I think your account might have been invited into a Teams organization. Please follow the recommended instructions below to leave the organization:
Open your Organizations page. (If you're using a work or school account, go to https://myaccount.microsoft.com for work/school account and My Account URL that includes your tenant's name or tenant ID for personal account.
Under Other organizations you collaborate with, find the organization that you want to leave, and then select Leave.
Note: It might take some time for this change to reflect in Teams.
However, in some cases, certain organizations might require you to contact their administrator directly to request the removal of your guest account from their organizations. Please use the provided information to get in touch with them and request their assistance.
Important: After you have removed an account or left an organization, the account might still appear in Teams due to caching. Therefore, clearing the Teams cache is also a recommended step to ensure the account is fully removed from your view. For instructions on how to do this, please refer to the Clear the Teams client cache - Microsoft Teams | Microsoft Learn
If there is any update or I misunderstand you, please feel free to let me know. I will continue to assist you. Your understanding and co-operation are highly appreciated.
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