Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> b13cd6afc9b6cfc3b2ae2faafbbc0bd072f8cfa1bc655255fef3e65dacaa9b29:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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