Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> a9f4345e0b7f1dde95ea58c5f373396c058ee9908b6d4d318dc9f291fe59a2fd:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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