81: Not enough balance paid down over time on student loans
The amount that has been paid down on your open or deferred student loans is low. People who haven't paid down much of their student loan balances are higher credit risk than people who have.
As monthly student loan account payments are made, a portion of the outstanding balance is reduced, benefitting your score. Whenever possible, further pay down balances on your accounts. Over time, this will also have a positive impact on your score.