Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> 942c30555ab848384a1220d100016d72c81aa1e217715d3aa62206a5e7909544:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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