MingChan

I have 2 campaigns setup with same setting - Campaign Type: Contract (Exclusive) - Start date: Start immediately - End date: Don't expire - Price model: CPM - Weight: 1 No limit on impressions And each campaign associated with 1 banner and linked to same zone. When I preview the website, it always displaying the same banner on that zone. Should it be randomized? I have 2 exclusive campaign with same weight, the banner should be selected randomly according to the weight value. Anyone have any clue on this case?