There are several education credits----which credit are you asking about? If you mean the American Opportunity Credit----you can use it up to 4 times during the time that you are in undergraduate school. You cannot use it after you have earned a bachelors degree. If you were claimed as a dependent at any time and your parents used it for you on their return, those times "count" toward the four time limit. So you might need to check with anyone who has claimed you while you were a student.
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