Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> a247555e95cfa64be1e05962daa28833c9d3390a6a67d4301d73a1aeb84e5a74:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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