OnPurchaseFailed,Duplicate transaction

Unity Services
1

Unity Version 5.6.3f1
IAP Version 1.18.0
Xcode Version 8.3.2
Failed in testing of IOS system
All items are consumables

My log output：
UnityChannel purchaseInfo: productCode = , gameOrderId = , orderQueryToken =
Duplicate transaction detected, unlock this item

Nothing in purchaseInfo，but PurchaseFailed！
How can I solve this Duplicate transaction？

2

Please provide steps for us to reproduce this issue and the code that you are using. Is this for Xiaomi (UnityChannel) ?