Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> 1186b4ad00641f7c8ac50cda76cebd7adc8a7b7c3e9f0749ddf2ef285307b7a3:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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