Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> 1477836dd38b3db208e7cb8bd857746c4af97341bbe79b7d52a67646ecd8db14:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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