Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> cf7b887dc8bd5a0b8894a035b8ef8062aaf598ba6bb5a3b83dd605fd8c5e3909:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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