Transaction

[Error Code: 1101] error caused by: 1 error occurred:
	* transaction execute failed: [Error Code: 1101] cadence runtime error: Execution failed:
  --> 7f470bc46fadb0adcb92f407f6e57b933a657acb35ee635871582ae0065fa8cb:72:20
   |
72 |         let item <- self.listing.purchase(
73 |             payment: <-self.paymentVault
74 |         )
   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

error: pre-condition failed: listing has already been purchased
   --> 4eb8a10cb9f87357.NFTStorefront:271:16