Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> 94b2b60ec5260fa81a74e3a90f29f8d6e8596a2ce384e8a7cd9be7e6fa01ffca:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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