Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> 56dc80a4b9d819a9b29a963aa9686a56e49959a980a567b0eefc387ff7cd7e6d:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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