Mopub ad does not appear when using personal ad unit ID

Question

I included Mopub in my Android project using Fabric. I can show a full-screen ad using a test id.

But when I use my personal ad unit identifier for an ad, it doesn’t work.

I believe that I installed the ad through the Marketplace on the Mopub toolbar, but maybe I missed something?

Here are the error logs:

D/MoPub: Failed to retrieve GPS location: access appears to be disabled.
D/MoPub: Failed to retrieve network location: access appears to be disabled.
I/MoPub: Ad failed to load.
D/MoPub: Interstitial load failed: No ads found.