Hi,
you have none on both your ids when initializing...
You need to inform the framework of your ids, you can find them in the "advanced tab" of the Ad service Inspector.
Which version of Unity are you using? the latest is strongly recommanded, as the Ad framework changed a lot, and this set of actions only work with 5.2+
I need to make a video, as the process is totally coutner intuitive and very misleading within Unity Service Inspector.
Bye,
Jean