Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> 20a9946a29d147ac0ccde74af24bace787b184d4503c1328b202f8b80e478049:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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