Only the account admin or a Staff user with billing permissions will be able to update or change the payment method on file.
How to update or change the payment method on file
To get started head to the Billing page by clicking Billing on the Home left sidebar, or clicking the user icon in the upper right then selecting Billing from the dropdown.
This will open the Subscription tab of the Billing page. From here scroll down to Payment Details section and click Update.
The Payment Details section will expand to reveal the required fields for your selected payment method.
If changing from Paypal to Credit Card or vice versa simply click the circle beside the payment opposite payment method and the form will update appropriately.
Fill out all the billing fields with your updated credit card or billing information, then click Save in the bottom left to lock in these changes for your next charge or renewal.
If you've switched to PayPal or have updated the company information clicking Save will redirect you to the PayPal website to login and enter or confirm payment details. Once finished you'll be directed back to the updated billing page.