Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> 13211993d1495b2e825abe16403623ac5a99d6aa53fac6b642de2f13420a8f22:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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