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Here's my write up. Pretty much same as @hairbag1
How to change your credit card number
First and foremost, if you are changing your credit card information, you need to add every piece of information about the credit card like it was your first time. Even if it’s already auto filled, do it anyway.
When you log in to your Public Mobile account, go to the Payments button.
On the right hand side, click on Manage Subscription.
Then click on Manage Payment Method and remember, change and edit everything even if it’s already auto filled.
When you've entered the credit card number and expire date, hit Manage Payment Method.
If this doesn't work, go into your browser settings, clear your cache, close browser and log back in and try again. Sometimes the website and your cache tend to fight. 🙂
Log in to your account Payment / Click on Manage Payment Method and you should get to area where you can edit your credit card deets.
