You can have multiple teams under the same user account and each team can be on a different subscription plan depending on how you run your content production and how large your team is.
That means you have the possibility of setting up different Payment methods and Billing details for each team as needed.
You can only add, replace or delete your Credit Card and Billing information if you're a Team Owner or a Team Admin.
To update your Credit Card, select the team you want from the upper left corner.
Go to Settings (bottom left corner - gear-like icon) and select Billing details. You can change your card info there and click the Save Changes button in the upper right corner, under Create.