Your Federal Refund may
have been Offset by the IRS.
A refund offset is
when an IRS refund is reduced or intercepted to pay off delinquent debt,
such as past-due child support, outstanding student loans, or unpaid state
income tax.
You'll get an explanatory
letter from the Bureau of the Fiscal
Service if your refund is offset. The remainder of your refund will be
processed as usual; an offset shouldn't delay it, unless of course your entire
refund was applied to your debt.
More info about refund offsets, including contact info and
the appeals process, is at IRS.gov (Tax Topic 203).
https://www.irs.gov/taxtopics/tc203.html
Or Call the IRS
Refund Offset Office at (800) 304-3107