Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> 56f9ee13f59559acb43811e90abe8599e90070a7f043369d1f3a0a10e703bd84:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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