Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> d9a2cfc4ec6d71100aef7f1ebf0ad20dd8d82f8d57392c4bbd44149241b889ad:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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