Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> 3a8eef5e759e16195fb34f99587d7a945fe56b788bce84cb6e48e1b163e74417:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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