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Thank you for the reply, but I probably should have mentioned that I had already read and tried all these options. None worked.
As it turns out, I needed to change my billing address.
I live outside the US and had listed my foreign address in my return. This is why it didn't accept payment with my American credit card. I had to go back and erase my foreign address and add an American billing address. Luckily I do have one, and the credit card info was finally accepted, but I don't know what to tell the other users who don't have an American address to list.
If you are encountering difficulties when using a credit card to pay your TurboTax fees, please confirm the card is an accepted payment method (VISA, MasterCard, American Express, or Discover) and that your contact information on file is accurate.
Please return to the MY INFO page in TurboTax and enter the same address as your credit or debit card you are using, go to the FILE tab to pay and make sure the credit card information matches exactly.
Please see this TurboTax FAQ for more information: https://ttlc.intuit.com/community/bugs-and-error-messages/help/error-your-payment-information-cannot...