Hawaiian Airlines refuses to refund our tickets

[Chas]

We never cancelled our tickets. We filled out their form to request a refund.
Two weeks before that, we received an email saying our flights were cancelled. It included the option of a full refund with no penalties.

Did you send those emails to the credit card company? I'm pretty sure that would be enough.

I was told once that in order to accept credit cards, merchants must agree that the burden of proof falls on THEM, not the consumer.