Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> 85ff559baae7214a30a0f41ad092497cbbcfb4ac7146c2922f5ed3598718501d:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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