Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> 0ef2668c34b6c941f47f401f10f20e99a01cc1a29e583da509b58e545f126ab0:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

error: pre-condition failed: listing has already been purchased
   --> 4eb8a10cb9f87357.NFTStorefront:243:16