Charged after account was cancelled

I purposefully cancelled my services with Verizon Fios well before the end of my billing cycle. I have the confirmation number. The representative I spoke with when I cancelled told me that I would not be charged again.

But today, Verizon charged my monthly payment.

I spoke to another representative through Chat and they "assured" me Verizon would send me a check / refund on July 5th.

Verizon has no problem taking (unauthorized) money from my account but I have to wait for a paper check for a refund for their error????

When you cancel a service, you are cancelling a service -- you should not be charged again. I have never heard of charging customers after they have cancelled, especially when a cancellation is made well before the close of a billing cycle.

Have other people experienced this? Did they make you wait for a paper check for your refund? How is this even okay?

I deeply regret signing up for Auto Pay (something I never do) but it saved me $10 a month on my bill. Never again.