Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> 3917460219b9fe0451dcc26e66c54d3fdbda85a66cdd7cc954773e2016930f8c:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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