Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> 9ab28428d7f81de2c55e0a6b84b00958021fe1bcd2ab6cd9d90d592cc683beb0:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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