If the username if specified in the remote for a particular repository you can edit those in the Remotes section of the Repository Settings for it. If you want to delete an account entirely you can do so in the Accounts section of Sourcetree's settings/preferences. Hope that helps.
Senior Mac Developer, Sourcetree
Supported Platforms macOS Windows We recently introduced support for additional hosting services such as GitHub Enterprise, GitLab (Cloud, Community Edition, Enterprise Edition), and...
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