Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> 89cbd2a4ee3c6ce5bd3961a8a7b499c2de731867ea5b124af8ed0e5f7527e9cf:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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