Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> 844e560e20b120272bae0f7dc50639e43384143f594204ae97e51443ccef32d1:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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