You will occasionally run into reporting discrepancies between your ad network reporting and the MoPub reporting numbers. Most often, these discrepancies are not signs of actual issues but just a nature of the way the various ad networks are integrated.
If you see discrepancies, please evaluate if the following issues apply to you.
Attempts vs. Requests Discrepancy: If you have not previously integrated a network SDK, and integrate it at a later time, there are versions of the app in the wild which won’t have the network SDK available to show ads. Our system makes attempts to all of the app versions and logs this behavior, but for those older app versions that don’t have the network SDK, the network won’t be able to log a request because the SDK isn’t there to communicate with the network.
You have an ad network integrated in a source outside of MoPub: If you have integrated an ad network in older versions of the app directly, or with a mediator other than MoPub AND are using the same ad network ID, the network will show more requests and impressions than MoPub does. To resolve this discrepancy you can either switch out the IDs (which is not suggested) or just wait until all of your users update to the version of your app with MoPub integrated.
Server to Server Interstitial Tracking: For server to server networks which show interstitials, we always fire off their impression trackers on load (due to them being in the body of the tag) but we fire off our impression tracker on show (which is more accurate), so this might cause a discrepancy.
If your issue is not resolved here, feel free to reach out to firstname.lastname@example.org .