Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> 999b1283f71e42d9f7281047a070bd67a4aee58143ad5e1b5d866c30b86d4824:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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