Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> ee309ff4f72f2d2ce3bbde7ef86e460ffa5b7241e56b5e85c9de4d8b36f65366:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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