Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> cc87600e0711a4eb2920dfd8d3ec58f7f2f07ea3bf261b081ffca164b0a1cf58:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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