Why can't i update my account payement ?

Jules

Can you please tell us a bit more? Do you have an error?

This is the procedure

If you need to add a new credit card
1- In your Fizz account, go to My Profile
2- Click on Payment methods.
3- Click on Add a new payment method to add your new payment method.
4- Now make your way to My plans.
5- For each of your plans, click on Manage plan/Payment method, and associate your new payment method.
6- Then, select the payment method you no longer want to us, and click on Delete.

If you associate a new credit card with your plans, you can also force the payment
My Plans - Manage Plan - Payment method - Make my monthly payment. Once payment has been made, your service will be restored within 2 hours.

In case of problem, you can contact Fizz support by chat

1- Log in to your account (see top right).
2- Any ad blocker in your browser must be disabled.
3- You must be on a help sheet: https://fizz.ca/en/faq/how-do-i-fix-payment-issue
4- The green bubble should appear in bottom right of the page

please tell us what happens. Do you get error message(s)?

I would contact customer service via their facebook page, they should be able to help you.
Note that they do not accept prepaid cards if that is what you are trying to do.