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
 --> f5ce4c0eb31d4aecd312bd23b1385fef47f05c09ca3aaf42a96e6d9be9b3e12f:6:54
  |
6 |                 if let listingResourceIDs: [UInt64] = storefrontRef.getListingIDs() {
  |                                                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected `optional`, got `[UInt64]`

error: value of type `Transaction` has no member `storefront`
 --> f5ce4c0eb31d4aecd312bd23b1385fef47f05c09ca3aaf42a96e6d9be9b3e12f:8:29
  |
8 |                         self.storefront.removeListing(listingResourceID: listingResourceID)
  |                              ^^^^^^^^^^ unknown member