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Turbo Tax is making a calculation error on line 12b on form 1040, when I do the final review, after state taxes, it changes my charitable donations from $600 to $300.  After oil does this it tells me I have an error and I need to change it back to $600. I save it and then go back through to check things and it does the same thing again, even though I saved it and it should be $600 in line 12b of form 1040 worksheet. I tried calling and the computer generated person, won't let me speak to a real human unless I have a purchased the rights to do so. This is not very good customer service and I'm not happy with this.