Hello,
Few more questions and comments that could help clarify the situation but it would be very helpful if we could get a Support Request with a full log and the content ID of your app so the team can review. If possible even access to the apk via a closed beta.
I assume that the purchaseID passed to consumuePurchasedItems is a valid one. Are you trying to consume an item after validating that the item can be consumed? Did you check for any errors in the onPayment callback?
The second parameter for consumePurchasedItems should be the name of the OnConsumePurchasedItemsListener` interface.
If you check with getOwnedlist API, do you see the item returned as non consumed?
Is this problem only affecting the onConsume callback? Are the other callbacks working correctly?