Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> 7947d2336ed0ded7951a5b85d506a6dcb2ff2467cb9cb79f506d87278c0c5ba5:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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