I got the error when I test the Samsung IAP SDK in Unity

I already setup the Samsung IAP V5 SDK in my game. And setup the iap item in the Seller Portal. This iap item is consumable item. I use the StartPayment method to do the purchase. I get a response in the first purchase. But I cannot purchase the item second times. And I always get below error message.

Original post: https://developer.samsung.com/forum/board/thread/view.do?boardName=SDK&messageId=378202

Since you have a consumable item, you will need to consume it first before trying to purchase it again. E9010 means he has not consumed the item. Call consumePurchasedItems to consume it before using startPayment again.