Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> c742f7a6ba7a5d322a1b69ac55d2760323e4eceeb7dd68f70fe0ce3a0eb2a42c:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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