Why hasn’t the buyer clicked the "Mark Received" button?

The "Mark Received" button is used when the item has been received by the buyer. If this has not been done yet, the buyer may not have received the item, or they have forgotten to do so. As a seller, you can send a friendly reminder to the buyer to press this button once they receive the item to complete the transaction. If the buyer is not responsive, the listing state will change after a certain time period.