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
 --> cd3b0f94bba56308c162b41b2e6ccf6f5f06113f8ca1c2d083cd6cf136c8cbbb:6:54
  |
6 |                 if let listingResourceIDs: [UInt64] = storefrontRef.getListingIDs() {
  |                                                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected `optional`, got `[UInt64]`

error: value of type `Transaction` has no member `storefront`
 --> cd3b0f94bba56308c162b41b2e6ccf6f5f06113f8ca1c2d083cd6cf136c8cbbb:8:29
  |
8 |                         self.storefront.removeListing(listingResourceID: listingResourceID)
  |                              ^^^^^^^^^^ unknown member