Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> aad3e2b53e9e8cc8e8815c95bf912f7df76d4e0c2ec0a85cef75b0dc68faaeb9:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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