Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> f56d3439e9b4da5581efb92a0842e7f0646a51339eb58fde3ad64b7740f62e04:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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