Item Already Owned ERROR MESSAGE with Unmanaged Item on Google Play Store

Question

Our android game is still under testing and not published yet. And find problem with In app purchasing.

Game does have bunch of CONSUMABLE ITEMS [Unmanaged] and it usually works correctly, however, it rarely returns [-1008: unknown error] from Google play. After then, if I try to buy again, it says "ITEMS ALREADY OWNED" which doesn't make sense because it is unmanaged item.

Please NOTE that it's not published yet and we have been testing with tester account registered on our Google Developer Account

Please advise.

Thank you

Answer 1

Are you consuming the product that was purchased on each purchase success?

http://developer.android.com/google/play/billing/api.html

see section "Managing consumable purchases in your application"