Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> 8eeb8f76fb3e07f6691733ec20a8d0a2e06b16df23b6f03fa024fc36d6e3c733:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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