Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> 6e3b169e1a035a308019c35a7f368a6743aca8dd6b47a65b1bb3fc8e10eb60e6:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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