Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> ad257e293b77433357ca3b91e4ce16758f5072d4a2183d2b143ce5bfea01f306:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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