Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> 78df15fd70cf2245d8572738a4719a51ae3bd2343daff3cfc1cdcf1c74590c02:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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