for the past 3 years i have been reasessed by Cra due to an age error . The age is entered properly in the turbo tax program

The only thing that it can be is either the CRA has a different date of birth on record/file for you than what you entered on the TurboTax and/or you entered your date of birth wrong- mixing up the month and day of your year of birth. Please double check that you enter your day of birth, month and then year. 

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