Copilot Agent inside SharePoint site is not able to answer questions regarding the custom columns

I have a SharePoint online document library named Test. and it has those 3 custom columns inside a custom content type:-

now using a username named Mohannad , i uploaded 2 documents, and for one document i defined a user named "Test User" as the "MC / Project Lead (Use)", as follow:-

but when i asked the agent this question, about who is the Project Lead , i did not get the "Test User", instead i get the user Mohanand:-

also when i ask the agent about the project team, i got this answer:-

so how i can modify this behavior?

Second question. when Copilot said that the document is authored by Mohannd, how it get the Author info? based on the created by field inside SharePoint? and can we create a custom column , so the copilot reads the author from it instead of relying on any built-in field?