Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> a5d665b4dfecb1b802cbdf15a3e13917ecd0d825f7ccd0d5e6a5c3b50eef6c1a:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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