Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> bf6e2b8fa10be382650e5f6d95e167c9fb941944e3e1d55dd6f496d5fc3923bc:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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