Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> 8b93ca99c457729f9c6acacade11d4e20ef43812dfbe69eabf93d291329c6f34:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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