Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> 7754f5b4f2a98f10d743fcd0860edd26aa08ad1c85188b58f50e1347fe044873:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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