Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> d4f206e6156f0c86c60c5f69ef4514de9e6640f2c21cf04fa8c3897ae6c2b471:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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