Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> 3b4a2e04561e6670e0f9fa60e8d9a5be9ed67e14a960eb79ce4c1abbcc90b034:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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