If you received your refund from the IRS and it wasn't the amount you were expecting, there may have been an offset. A refund offset is when the IRS intercepts it to pay off a delinquent debt, such as past-due child support, outstanding student loans, or unpaid federal/state income tax.
The IRS will mail you a letter explaining the change in your refund.
For more information about refund offsets, including contact info and the appeals process, please see IRS.gov (Tax Topic 203).
In addition, here is a TurboTax Help Article: Why is my refund amount lower than the one shown in TurboTax?