Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> 86064929911094006988341c1402143197524fef4a810a1798798d83a0d2a9ad:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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