Within Teamwork Chat, you can update your payment details via your subscription settings.
This article refers to accounts on legacy Teamwork Chat Pro subscriptions.
To access your subscription, click your profile icon in the top right of your site and select Subscription from the dropdown menu.
Below your subscription summary, click the green Update payment details button.
You will be brought to the checkout area where you can put in your updated payment information, as well as contact details and any changes in billing address. On the right-hand side, you will see a summary of your order as well as options for adding a tax number and whether to make the invoices out to the account name for your site or enter in a different reference.
Click Update to save your changes.
For more information, see: Creating a Teamwork Chat Subscription