Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> 85960b7fe4276e188dcb474a9b57df6038b584b3cb9d0758575d9df7af9169c4:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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