Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> 18999d4cc52caa0d338fb767d70eeed6b4c326c48de0aabacfee98bf83937670:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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