Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> e820ff9a1ae12a4a9aef5a41f972cca0355e2a7c8d4bb6b26237dd9aadecd5f7:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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