Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> b1384f9ceec88bacf88bf016787e8c3aea30ecc13e76473be2b29a81bb15afa8:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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