Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> 76f8e12105a8e753eb381b67b82289f2b90973002de232f4c1861a7bd57a751d:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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