As Mike said, this is the user community where we try to help each other with various issues that can be solved without getting Fizz involved. Payments, however, are obviously something beyond our control. Your best bet is to try to get the Fizz Support Team on Chat from the Solutions Hub page within their business hours (Monday to Friday from 8 a.m. to 9 p.m. EST, weekends and holidays from 10 a.m. to 6 p.m. EST). They also respond on Twitter and Facebook Messenger.
Which service are you subscribing to? Mobile, Internet or both?
Did you check by logging into your account? Under your plan, transaction history shows the dates and amounts of each payment. when did you activate service? What are the dates you were charged?
Fizz is prepaid service. So Fizz will charge you before they provide service and then again every 30 days when your next renewal is due.
If Fizz did overcharge you, then gather screenshots and credit card proof you will need to show Fizz customer service. Once you contact Fizz, they will investigate and refund you accordingly.