Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> 4dc3a30e28ca5c044fb23b335a21df6a31538c3e1dd5f7530939fb7cf73d1bd1:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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