Change the Name of Internet account to my wife's name

For this kind of request you need to contact Fizz. You can do so by opening a help page ( exemple https://fizz.ca/en/faq/im-unable-log-my-fizz-account-what... ). You'll see a bubble chat in the next 15 seconds at the bottom right of the page

You can contact fizz by chat or Facebook messenger :)

We are a community of customers like you and don't have access to your account. This is why we are redirecting you to chat in order to do this.

They usually reply the next day on Facebook.

You can not. I asked the same question with Fizz by chatting, and they told me I can not simply transfer. I have to cancel one and re-open another.

Why not you just use her credit to pay instead? Fizz probably say no for you already.