Cancelled subscription was charged

I canceled my subscription but I was still charged. How do I contact you to ask for my money back?

I believe you got an answer from support.
Any invoices you got were for the amount of $0.00. We do not charge after an account is canceled.

I got an answer, but the payment is on my credit card.

Please follow up with 8x8 support, we cannot help you with that here.