This error occurs when the return label's cost exceeds the product's return value. With Returnly, all products being returned must have a value that exceeds the labels cost.
Why? Returnly deducts the shipping cost from the Shoppers refund. This means there must be enough refund to cover the cost of the shipping.
Do you offer free shipping, and want to accept product(s) regardless of refund value? Just let us know and we can disable this setting.