Avoiding refunding incorrect charges

Can I add zero stars? I am from australia and needed a temporary mobile service while here. I entered and order online which Rain duplicated, and then took payment for both. Upon trying to complete the order, I could not validate my address as it was Australian. They don’t allow foreign addresses (ie. I could not access the service). rain will not cancel the orders and will not refund my money. Their customer service basically ignores my requests and does not respond to my DMs. I have had to ask Mastercard to intervene and recover my money. Lucky I had that fallback.