You are not authorized to make purchases of this InApp in Sandbox at this time

Hello,

Our app is experiencing an unusual bug.

Some users are relating that when trying to do an InApp purchase of our service they are seeing a pop-up with the following message:

We can reproduce this behavior in some test devices we have. We tested on iPhone 5, 5s and 6 (the ones we have) with iOS 8.1, 8.0 and 7.1.

But it is not happen every time. On another devices we tested too, we could purchase with no problems. Also, our revenue on iTunes Connect continues to increase and we can check on our database purchases from the latest zoo version.

Even though the latest version of our app was released on February 13th, this behavior started to happen yesterday (Feb 25th).

The message is showing on the version from App Store with normal Apple IDs (no Sandbox IDs).

Has anyone had this problem or know a solution?