When a product is processed through Shiptheory for the first time, it gets saved to the Shiptheory database with all the information it was processed with (price, weight, SKU, name, etc.)
If the details of the product have changed since it's first shipment (other than the price and weight which get updated each time) then the new name won't display.
The name can be manually updated in your products page in Shiptheory however if you search for it and edit.