Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> f7724899e4aaa287b6a80715ac9c1663c8f21d3b4a5cb6f8a3b1540cb27587f4:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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