Transaction

[Error Code: 1101] error caused by: 1 error occurred:
	* transaction execute failed: [Error Code: 1101] cadence runtime error: Execution failed:
  --> 990717e464042a0bdaf004ef032b68f32e368e8565570da29344f0a65f5a6d64:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

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