Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> b8e451bbcfb002af40fa77dc1cde6b52de4ad6a6bfc463fc02f0bbe16707975e:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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