When a customer creates a request, the return method is created depending on what method they selected. There is a possibility that an error may occur when creating the return label. The most common errors are because the customer typed the wrong sender address, or in international returns, the custom information for the items that are being returned is missing

To locate these requests, you can apply the following filter in the Merchant Dashboard :

You can find a guide to fix the most common errors when creating return labels, here.