In-app purchases are failing for some of our test users at the payment stage. Just after entering the PIN, they receive the message:
'Request not complete'
'A problem occurred when trying to complete your request. this can be caused by entering incorrect information or trying to complete an unauthorised action'
The payment information and PIN are definitely correct. I have just verified this with a newly made test user account.
IAPs are still working correctly for other test users in our organization using the same app build.