Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> 11ffa4fcb2b490137d5dec717de79589b2d46e51c000fd844db816926cd991c2:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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