As a maker, you can always cancel a listing (or any other order) - the Acilia NFT Swap API makes this trivial.
Any order created from the Acilia NFT Swap API can be filled or cancelled without the need to the same API. The orders generated by this API are simple 0x orders and can be cancelled by interacting with the smart contracts directly or with Trader SDK libraries.
Step 1: Request cancellation call-data
Pass in the AciliaID from the previous Listing request
# Using the same `send_transaction` code in the previous examples.
# This example assumes that Bob's address is 0x26970ceb166b71db3480b7464387f793a570259a
send_transaction(operation['transaction'], BOB_PK)
Step 3: Ensure the transaction succeeds
Ensure the transaction is correctly mined - and check the transaction logs to ensure the cancellation is successful.