Azure DevOps: Unable to Add Users to Individual Codebases — Permission and Organization Ownership Issue

Problem description

I am experiencing an issue with Azure DevOps Services where I cannot add users to an existing project or grant them access to specific codebases. The controls to add or change users are grayed out, and I suspect it relates to my current permissions or organization ownership status.

Environment

Azure DevOps Services, an existing organization with several project, affecting project membership/security and Git repository access within that project.

What I've already tried

I have attempted to add users through the web portal but the 'Add users' button is disabled or unresponsive. I verified the organization policies and my account's permissions, and I checked the organization settings to confirm the current owner. I also reviewed documentation on adding users and repository permissions.

Current status

Currently, I am unable to add users or modify organization owner settings. I seek guidance on restoring administrative permissions or changing organization ownership to resolve the issue.