See what PayPal support says:
I acknowledged that there is no item description in your receipt if your customers pay you via Express Checkout. But it is normal if they pay you via PayPal Standard.
By checking this transaction #05D27179N41925103 in your attached receipt, I found that the item description should be "TravelSat-V2 Portable VAST Satellite TV Kit (DELUXE)", right?
Because by checking your API request information of SetExpressCheckout API and GetExpressCheckoutDetails API, I found that you passed the parameter "paymentrequest_0_name" as "TravelSat-V2 Portable VAST Satellite TV Kit (DELUXE)". However, there is no such information in the last DoExpressCheckoutPayment API.
So, you are advised to contact Hikashop to ask if you or they can pass this parameter "paymentrequest_0_name" in DoExpressCheckoutPayment API so that the item description (item name) can be displayed in your receipt.