Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> b6e0cd6f9f98fd2b8831c6ac525535456122c3ce73f8fab143883b92ff3f9b1d:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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