Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> 4340b79fa40dc8647150950d65a240b88a3ceeb5d322ca4fb66ca65691769316:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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