Transaction

[Error Code: 1101] error caused by: 1 error occurred:
	* transaction invocation failed when executing transaction: [Error Code: 1101] cadence runtime error: Execution failed:
error: mismatched types
 --> 3cdf4b954e7cf1a79c4e54a3cc8f2064f78be79ff18a7af9a7a3c7687c86f77d:6:54
  |
6 |                 if let listingResourceIDs: [UInt64] = storefrontRef.getListingIDs() {
  |                                                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected `optional`, got `[UInt64]`

error: value of type `Transaction` has no member `storefront`
 --> 3cdf4b954e7cf1a79c4e54a3cc8f2064f78be79ff18a7af9a7a3c7687c86f77d:8:29
  |
8 |                         self.storefront.removeListing(listingResourceID: listingResourceID)
  |                              ^^^^^^^^^^ unknown member