It is not a feature that can be shut off in an organization or a project’s settings. Double check your organization and project at upper-left on the platform site is your funded org that used it before.
I would suggest: disable any extensions or ad-blockers, and hard-refresh the platform site page. If still not appearing, but you can get Agent Builder on a different browser or device, you may need to delete stored a browsers local data for platform.openai.com, and then extending to others like chatgpt.com, openai.com, auth.openai.com, auth0.openai.com.