Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> 702870b8c247e93e60a376e3e79b8dffad73b577c95adc1fecd50916660d7cd6:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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