Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> 5cd61ac70cf0cd3ab8af4d8ce8c58c39ad08582f1fd3e3623ed44d247f4bb4b0:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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