I'm not sure, so hopefully others will chime in. I believe that support of Google's Double Click for Publishers is not supported for banners. Banners are static only images at this time, and allow you to specify a click through URL to launch a slide up web view.
Should I ask the adobe support? I have an HTML article with a DFP script, but I can't see any content in my app. It would be great if adobe could check my article file.
Yes, you should contact Adobe support and they can look at your article file. If you're trying to use DFP as a banner, to be displayed as a banner, that's not supported. If you are using DFP inside the article when the full article is displayed, then perhaps there is an issue with how the banner is added to the article. Either way, you won't be able to see the DFP ad in the card/grid browse view, it would only be displayed in the article when you open it up