Can a customer request refunds for products that are not shipped yet?
The RMA extension allows creating refund requests only for those products that have obtained the Shipped status.
This logic is based on the idea that, until an item has been shipped, there is nothing to physically return. Therefore, the most appropriate scenario for an order that has not yet been shipped is order cancellation rather than an RMA request.
To allow customers to cancel orders for items that have not yet been shipped, we'd recommend enabling the default Magento setting at Stores > Configuration > Sales > Sales > Order cancellation > Order cancellation through GraphQL = Yes. This setting not only allows cancellations via GraphQL but also activates the Cancel Order button directly on the My Orders page of your storefront.
As a result, the Cancel Order button will be available to your customers when applicable: 