Adsense code

Hey.

I have a wordpress simple webpage and what is wrong with Google Adsense? When I put a Ads code (Does not matter or it is Synchronous, or Asynchronous) what I can see is just empty place, sometime it white, yellow, blue boxes ,it is depends which theme Iam using. Who knows what is wrong here?

Yes, my Google Adsense account is confirmed.

Thanks!