Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> 479d5a8ad346acfe99f8d5c4249a376d5f8b02a04556e125d170cc88ab46cd46:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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