Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> 6200fa73a148359b739f1b9f3f640fd536847b0645534b003d751c04e0daef21:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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