Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> 4f711e798e1089dab279b8543c3cad9aa34f662d7952d4958835e5039f220d0d:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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