Account Performance Report always returns empty reports for Display Network

I am using the latest 201605 API. While it is fine getting *Search Network *data (AdNetworkType2 = SEARCH) from* Account Performance Report*; for *Display Network * (AdNetworkType2 = CONTENT), it always returns an empty report. (or all zeros when includeZeroImpressions is set to TRUE) I tried

Re: Ad Performance reports with AdNetworkType1 or 2 fields or predicates, returns empty report

I know this is an old thread but I am experiencing the same problem now... While it is fine getting *Search Network* data from* Account Performance Report*, for *Display Network*, it always returns zero. I tried to include AdNetworkType1 and AdNetworkType2 fields (no Id and AdGroupId fields in