This could be a web browser issue so try a different web browser when updating your CC information.
Or contact TurboTax customer service/support use their contact website during business hours. Use the key words billing issues
Use this website to contact TurboTax support during business hours - https://support.turbotax.intuit.com/contact/
Support can also be reached by messaging them on these pages https://www.facebook.com/turbotax/ and https://twitter.com/TeamTurboTax
