Google Nexus 5 :: Doesn't Appear In Play Store Or ADM

I activated a Nexus 5 on Sprint back in March.

however is that the phone does not appear in my device listing in the Play Store when I access it on a computer, or on Android Device Manager when I access it from a computer or from the phone itself! I can access the Play Store just fine from the phone, but cannot install apps from a computer. From the Play Store or ADM I can see my Nexus 7 and my old phone, but not the Nexus 5. The phone is set up with the same Google account as the other devices.