Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> a408365d479bc3e2d40ded61578285ff2cef8fe4649d064ce8c4f1c013f14838:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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