Ad requests never filled with AdMob

Well, I get this message all the time using AdWhirl:

Unable to fill ad request. This is a common situation.

I think开发者_如何转开发 it's from the AdMob network. I also have a couple of other networks (registered yesterday) and I never seem to be getting any ad requests filled. In test mode it does work though. Now is this common and will it pick up?

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Turns out it went away after a couple of days. I guess AbMob had to review the application first.

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Not only is this normal when the app is new, but it is also more frequent depending on your geographic location. In Switzerland I had ads all the time. While I am here in Brazil now I face much more often the "no inventory" issue.

In any case you can't do much about it, other than to rollover to another fallback network if you use Adwhirl or a similar solution.