Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> 140a7aa78d5ee284374e8f09783eda3cde70d7379fd0310741617f67e19fd716:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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