What was the error in the TurboTax calculations? What did the IRS say was wrong in your tax return? What did the IRS change in your tax return (besides the amount of the refund)?
You said you submitted documents to the IRS. What documents did they ask for? Were they documents that you did not enter in TurboTax? Did you make an error entering one or more of the documents into TurboTax? Almost all tax return errors turn out to be caused by incorrect or incomplete entries.
The TurboTax Maximum Refund Guarantee only says that you will not get a larger refund using another tax preparation method.
You can contact TurboTax by following the instructions at this link. If you are asked what you are calling about say "billing issue." Do not use the word "refund."
