Google In app billing always failing and not consuming

Question

Im trying to add in app billing that will allow the user to make a purchase as many times as they like (no limit). Therefore it must be consumed. The first time I run the code on a new device it works fine and the test purchase is made successfully. However it fails to be consumed and doesnt let me make another purchase. The problem seems to be in this method, as it always ends up with result.isFailure() thus, the purchase is not consumed (and can only be made once).

IabHelper.OnIabPurchaseFinishedListener mPurchaseFinishedListener = new IabHelper.OnIabPurchaseFinishedListener() {
    public void onIabPurchaseFinished(IabResult result, Purchase purchase) 
    {
        if (result.isFailure()) {
            Toast.makeText(getApplicationContext(), "Failed to make purchase.", Toast.LENGTH_LONG).show();
            return;
        }      
        else if (purchase.getSku().equals(ITEM_SKU)) {
            consumeItem();
        }

    }
};

Does anyone know how I can fix the problem?

Here is the rest of the code:

    Preference removeAds = (Preference) findPreference("inAppBilling");
        removeAds.setOnPreferenceClickListener(new OnPreferenceClickListener() {
            public boolean onPreferenceClick(Preference preference) {

                mHelper.launchPurchaseFlow(About.this, ITEM_SKU, 10001, mPurchaseFinishedListener, "mypurchasetoken");

                return true; 
            }
    });

    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) 
    {
        if (!mHelper.handleActivityResult(requestCode, resultCode, data)) {     
            super.onActivityResult(requestCode, resultCode, data);
        }
    }

    IabHelper.OnIabPurchaseFinishedListener mPurchaseFinishedListener = new IabHelper.OnIabPurchaseFinishedListener() {
        public void onIabPurchaseFinished(IabResult result, Purchase purchase) 
        {
            if (result.isFailure()) {
                Toast.makeText(getApplicationContext(), "Failed to make purchase.", Toast.LENGTH_LONG).show();
                return;
            }      
            else if (purchase.getSku().equals(ITEM_SKU)) {
                consumeItem();
            }

        }
    };

    public void consumeItem() {
        mHelper.queryInventoryAsync(mReceivedInventoryListener);
    }

    IabHelper.QueryInventoryFinishedListener mReceivedInventoryListener = new IabHelper.QueryInventoryFinishedListener() {
        public void onQueryInventoryFinished(IabResult result, Inventory inventory) {
            if (result.isFailure()) {
                // Handle failure               
            } else {
                mHelper.consumeAsync(inventory.getPurchase(ITEM_SKU), mConsumeFinishedListener);
            }
        }
    };

    IabHelper.OnConsumeFinishedListener mConsumeFinishedListener = new IabHelper.OnConsumeFinishedListener() {
        public void onConsumeFinished(Purchase purchase, IabResult result) {
            if (result.isSuccess()) {                
                CustomAlerts.showBasicAlert("Thanks", "We appreciate your support.", About.this);
            } else {
                // handle error
            }
        }
    };

    @Override
    public void onDestroy() {
        super.onDestroy();
        if (mHelper != null) mHelper.dispose();
        mHelper = null;
    }

Answer 1

You need to query the users inventory on app start. If there are any purchased but not yet redeemed products in it, you can just redeem them at this point. Here's the docu for retrieving it.