Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> 20071c4f9aa440773942ba1e2b0a8b72337e7ef55902799ef8a86c1a77bd5faa:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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