Adsense hosted upgrade to content need help?

I signed up adsense through youtube, so my account is hosted.
I have upgraded to content acc, via my site.
They informed that I must make code, and put them on my website, I have created the code and follow the instructions (posted on my site).
But I had to wait several weeks without notification about the start of my review sites.
Also there are no ads appear blank, I need to do?