App Store Connect is showing another as account holder even while I'm logged in

Hi, I am a a team member of my client's app. I just renewed my own developer account and was trying to add my own team member for my own new app, and when I go to App Store Connect to add the team member, it shows the account holder as the account holder for my client's app, and me as a team member of their app. How can I add my own team member to my own app, even though I am a team member (and non-account-holder) of my client's app?

Thanks for your help!