I am trying to add a new subscriber. I've gone through the steps a few times now over the course of 24+ hours and they still are not showing up. I follow the steps of clicking the "add subscribers" button, selecting "add a single subscriber", enter their first name, email address and a tag followed by hitting "save". So I guess 2 questions - am I doing this wrong? how long does it take for a subscriber to show up on your list?