Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> 7799c54dbc2a2c97a10570bc35d393c1ddb6fbafcd70abaa0e734a4260af4851:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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