Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> 7f5eae3d4954eb0cb84c93d1f20c8dd7bf4b408f2786092d20bf765fa044da47:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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