Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> 77a3293c5d2c05c711afb1ba7b7ccb030b1772e3e0ad686ae0d32dfa77b9bdb5:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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