Unless you buy data from Spartan (which you aren’t because you are buying data from AT&Tj, your Spartan account won’t show data. That part is correct.
On the portal, did you use MY CAMERAS > MOBILE ACCESS to create an admin access code for your camera? Once you do that, in the app, Account, tap the +, enter your account number and admin code, Save, Done, then tap Authenticate. Then tap Home and your camera should be there.