To access your account - https://myturbotax.intuit.com/
You have to sign onto your online account using the exact same user ID you used to create the online account.
Close all TurboTax windows on your web browser (including this one). Copy and paste the account recovery website link onto a new web browser window and run the tool.
Use this TurboTax account recovery website to get a list of all the user ID's for an email address. Run the tool against any email addresses you may have used - https://myturbotax.intuit.com/account-recovery
If none of the user ID's received will access your account, then use the option shown in blue on the account recovery website, "Try something else"
To update/change your credit card information - https://shopping.turbotax.intuit.com/unified/downloads/myaccounts?route=myaccounts&cgcview=billing
I have changed my credit card twice and you still request a new one because you are using an old card. PLEASE get this straight!!!
If you have already changed your CC information using the links from the answer above, then contact TurboTax support for assistance. Use Billing Issues as your problem
Support is open from 5am to 5pm Pacific time, Monday thru Friday
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