If you believe your purchase should have received 3x rewards, you can file a ticket with support by going into your account dashboard, clicking the transaction you believe was categorized incorrectly, and then clicking "Report an issue" at the bottom of the transaction screen. Follow the prompts to file a ticket with our support team and we will look into it.
If we agree based on our review that it should have qualified, then you will see that change reflected in your account. If we do not, we will let you know why via email.