I changed my plan and paid it today. I was not getting a confirmation of payment so tried 2 times more. Low and behold I 3 payments. Please refund the $86.00 overpayment.
You probably got credit into your account for the future months of service. So you have $86.00 worth of credits to be used for payment for future months. Unlikely you will get a refund. But you can always try.