Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> 6b772ba7d6e0335fa0f05e345cadb0028b98ddcb4c61e7f2f695fb3a1e97ce59:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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