Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> 339f3bbb2890b50afefad0a3f2d9c31ff713027c1bd026f7fc5954470de546bd:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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