Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> 2ffc57b5cf5a5e97f45b18fc569a04be8704b7d8f5d24f2440d041b4465d76bb:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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