Withheld too much from what? Your paychecks? That would be shown on your W-2 (s) and you enter it when you enter box 2 of your W-2. Or if you had tax withheld from other income, it varies with the document you are entering--but tax withheld will be on the documents. Do you have some sort of 1099's that show tax withheld? There are about two dozen kinds of 1099's.
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