Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> 2acc03a177f215a66ab66c4b7ff1d6cf27e3bfeaf1690038f00c4b7f3e4fb564:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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