hardy

Hi I have some different campains with different zones and banners. Since week ago some banners dont show again, into the Zone Information i can see the Banners but into de Statistik i can see, that the Banners are not delivery. if i start a new campain it's also not possible to delivery. I am a Senior user with OpenX and revive and they are not inactive campains and something else... Can me somebody help please? Thank you.