Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> 276a337f4ba830f95d9444ed4f679cc5b5f2e87f0339d0fce0d2d72b2c9f65c5:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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