Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> 1b4727bebcf3df404a18e69e152e77e5a6a64348409f9308447e9c6477bdc69c:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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