You can delete your credit card information If your subscription is completely canceled.
You are not able to delete it if you have an active subscription. Even if you cancel your account, it's still active until the end of the billing cycle.
Steps on how to delete your card after your subscription is completely canceled.
1. Log in to your Streamline web app and click 'Account > My Account.
2. Then, click 'Manage My Subscription'.
3. Then, click 'X' to delete your credit card information.