Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> b7c9a2404f7458c8624910fd03bcd19ab1d13143b16c4e08018bf39ba512e6f2:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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