Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> c4cf921ccdbaedbb248020710ce45e467c215884283d4f923b2b9e8ffc0b0d19:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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