First, check the front of your 1040 (lines 6a-d) and make sure all your dependents are correctly showing. Your total number of exemptions should be on line 6d.
Also, exemptions are subject to a phase out, which means when your adjusted gross income (AGI) hits a certain level, you have to start to reducing the amount of exemption you can take.
For 2016, the phaseout begins at the following amounts by filing status:
Married filing separately $155,650
Single $259,400
Head of household $285,350
Married filing jointly $311,300
Qualifying widow(er) $311,300
You must reduce the dollar amount of your exemptions by 2% for each $2,500, or part of $2,500 ($1,250 if you are married filing separately), that your AGI exceeds the amount shown above for your filing status. If your AGI exceeds the amount shown above by more than $122,500 ($61,250 if married filing separately), the amount of your deduction for exemptions is reduced to zero.