If you're using a standard Aerva media player (not a web player), then the issue may be that you turned on reporting while the player was offline in AerWave. In this case, please check the media player's internet connection. Once it comes back online in AerWave, it will synchronize with the server and start generating report data.
If you're using an Aerva Web Player (non-physical player that's viewable via a web browser), keep in mind that a Web Player does not generate content reports, so you will not see any data in that section. You will only see associated data in the player reports section.