Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> 23bb6e5ecab4f7f4d18eeaa472d112cc30f8f97956b3296cf911e0e0bbf0c41b:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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