How does one think they got a high school diploma but they actually don't have one?
This may occur because your high school is a diploma mill that charges a student a fee and requires him or her to complete little or no course work to get the diploma.
What happens if I accidentally received more federal student loan or grant money than I was supposed to receive?
In this case you would need to repay the amount that was given above the maximum you were allowed to receive by repaying it all at once or make arrangements to repay some at a time.