Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> 784bdeb2ccbed40e6c5c47643f37815f73726017b8d1db52e6c3cb3870909f2e:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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