Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> 31e4cc2fa4cad091e9a909713ba071e0aa4c022320a3d71c5094010de0b88a00:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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