Why isn't one of my ads showing?

One common issue is that if the ad has a different dimension (width x height) than the dimensions specified in the serving code, it will not be included in the rotation. Therefore, it will not be served to your visitors.

Example

Zone X has ad A,B,C. Ad A & B are 468x60 while ad C is 480x60. The serving code you have is for 468x60 so the rotation only includes ad A & B. On the other hand, if your serving code specifies 480x60 then only ad C is served.

Resize Ad Dimension

The first solution is to resize the banner so it matches the other ads in the zone.

Serve multiple ad dimensions

Another alternative is to serve multiple ad dimensions with just one serving code. When getting the serving code for the zone, remember to select all the ad dimensions that you want to show.