Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> b8dff57665b0f2ac8f23cb9d6e53e00efecaf6ed1a4e3fcb5b87e5c28f7a1c21:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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