Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> 6ed2695d5191457fe349a8242cd8ef8989d9ba27c0550ee7c117faffe02d4927:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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