How can I remove a project number from a users history?

Summary:

User has a project number auto populating in expenses that even when removed, reappears on the submitted report, whether they or a delegate submits the expense. They have never claimed from this project.

Content (required):

User has never claimed from the project, but it appears everywhere, including in the dropdown for "apply project" feature

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Code Snippet (add any code snippets that support your topic, if applicable):