Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> 207d113983ee5d5316166affb6b9c217823062024348c133cf37449beebb4351:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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