Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> 87fa2172535902b721b538b9929ea4c897c66183b798fc35e1101f3408807400:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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