Unable to get purchase flow started for a Subscription type Product on Google Play

Hi! I registered two in-app products on Google Play. One Unlockable Managed Product and another Consumable Subscription type product. Then following the instruction given in 'Qt Purchasing' documentation I added the required code. However, I can successfully start purchase flow (call purchase() method) on Unlockable Managed Product but when I call purchase() on the Consumable Subscription Type product, I get error Attempted to purchase unregistered product

Here is my code

Code:

---

Store
    {
        id: globalInAppStore
        Product
        {
            id: tbiosUnlockable
            identifier: "tbios_drugquery_temp_prod"
            type: Product.Unlockable
            onPurchaseFailed: {
                console.log("purchase failed!", transaction.orderId)
            }
            onPurchaseSucceeded: {
                console.log("purchase succeeded!", transaction.orderId)
            }
        }
        Product
        {
            id: tbiosYearlySubscription
            identifier: "tbios_drugquery_inappsub_yearly"
            type: Product.Consumable
            onStatusChanged: {
                switch (status)
                {
                  case Product.PendingRegistration: console.debug("Registering " + identifier); break
                  case Product.Registered: console.debug(identifier + " registered with price " + price); break
                  case Product.Unknown: console.debug(identifier + " was not found in the market place"); break
                }
            }
            onPurchaseFailed: {
                console.log("purchase failed!", transaction.orderId)
            }
            onPurchaseSucceeded: {
                console.log("purchase succeeded!", transaction.orderId)
            }
        }
    }

---

And I call it like

Code:

---

tbiosYearlySubscription.purchase();
tbiosUnlockable.purchase();

---

Any idea what could be causing this issue?