Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> 85c2a71e3b46894b92390a50f99f2caed6d368b11b55b0e1963436f7b570fbb3:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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