In App Purchase, not found list items

Dear my partner,

I have a problems with in app purchase.

My system can't show items list of it.

We used code sample off apple but it's still error. And i get notice: "Product Request Status: Cannot connect to iTunes Store"

We have downloaded and used sample of apple on the page: https://developer.apple.com/library/prerelease/ios/samplecode/sc1991/Introductio n/Intro.html

List items:

"aumobile.usd.099",

"aumobile.usd.499",

"aumobile.usd.999",

"aumobile.usd.2499",

"aumobile.usd.4999",

"aumobile.usd.9999"

Please help us check it. Or tell me how to we fix this problem?

Thanks so much.