Millennial Media SDK version 6.0 integration with Fabric


I have integrated Fabric in my android app and using mediation for 3rd party ad network. I have integrated Millennial Media SDK version 6.0 in my app and trying to mediate it through Fabric.

To do that I have created a directory com.mopub.mobileads and have put the latest Mopub Millennial adapter in it.

Now I am getting this in logs after I am trying to fetch the ad.

"Millennial Interstitial Ad - load failed (5): null"
Here err.getErrorCode() = 5 and err.getDescription() = null

Can someone confirm whether this is a fill issue or an integration issue? And if it is an integration issue what am I doing wrong as Mopub marketplace ads are working fine with this integration.