Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> 42eb79d54c92061268ebdc52601e52d61ce9fac2745966f401a4f55406658c7f:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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