[Plugin: AdSense Manager] Adroll ad doesn’t show anything

After using Adsense for a while I now started adroll. When I inserted the adroll.com adcode it recognized it as such and created a adroll ad. But when I put the widget in place nothing happened: no ad is showing (there is the adsense default ad saved on adroll, so this must show if it works). I reapeted this process, nothing changed.

To prove that the adcode itself works: if I use it as a HTML-Code in “Adsense Manager”, it works perfectly. But then, it is not recognized as adroll in the manager.

How can this be corrected?
Thanks.