I only get this option see the picture below
log in to your account on a laptop. Payment / Manage Subscription / Manage Payment Method...
you can easily do it yourself
To update your credit card information, you can easily done that via My Account
Please login to My Account, go to Payment page, click Manage Subscription, and click Manage Payment Method, or use this direct link: https://myaccount.publicmobile.ca/en/account/payment/manage-card
