Paid account from Sandbox, can't add emails or add new application

I have a Sandbox account.

I upgraded to a paid account. I can’t add any more emails. I can’t add an application. I can’t add any grants. It’s greyed out. I reached out to support but they haven’t helped. How can I add emails?

Hello. Our Support team has reached out to you via email to continue this investigation. Please check your mailbox for our message.