question

I have a strange problem with Amazon mobile ads. First I created an android app. Then I integrate with ads api, which require me to create an application. I did and it works. Later, when I try to publish my app in Amazon market, I accidentally created another App. I use it to publish to amazon market. However, if I use the new app's application id, the ads never shown, I have to use the old one to make it work. Anyone knows why? I have two apps and if I only change the application id to another, it won't work. Thanks!