Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> 766f6b5eba4c1abf58e8f8e9fffb7194818b0f323a659df0c1b5ea7db0cfbab1:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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