Failing to purchase IAP due to authorization issue using the production environment

I am getting the following error while testing in app purchase with a valid user account(not Sandbox user).

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


My App is in "Pending for Developer Release". Downloaded via TestFlight.

the iTunes account used for the purchase test is NOT a Sandbox user nor a tester.

happened on iOS11 and iOS10.

Is it because the app was downloaded via TestFlight? or the app current state?

Failing to purchase IAP due to authorization issue using the production environment
 
 
Q