Every member must have an active credit card on file in case any additional fees are incurred such as exceeding ride time in a given day, locking outside of a station or the service area, or for damage to or loss of bike.
On the BIKETOWN website:
If your billing information changes, log into your BIKETOWN account, navigate to your user account page, select Memberships in the left side menu, click the green edit pencil and add your new credit card information.
In the BIKETOWN app:
Navigate to the menu in the upper right corner, select Memberships, Add new credit card.