I called in and it took a while but the agent eventually agreed to refund the miles and taxes. However, I purchased the flight using a Chase bank credit card 50,000 flight reward certificate (points voucher). This certificate was made available to US credit card customers. The original e-mail cancellation indicated that this would be refunded but the agent on the phone didn't really understand what this as. He sent an email confirmation indicating the miles/taxes would be refunded but I don't see anything about the voucher. Does anyone know an e-mail address I can use to help resolve this? I have a feeling the phone agents won't understand. The original cancellation e-mail shows:

RefundDate of issue: 20 Dec, 2022
21,900 pts+ CA $70.78
+ 11 Credits+1 Flight Reward Certificate