Did you opt for the Refund Processing Service (also called pay-with-your-refund)? It gives you the option to deduct your TurboTax fees from your federal tax refund.
Or You might have a refund offset:
If so you will receive a notice explaining the refund offset. The offset could have been from delinquent debt, such as past-due child support, outstanding student loans, or unpaid state income tax. The notice will reflect the original refund amount, your offset amount, the agency receiving the payment, and the address and telephone number of the agency. https://ttlc.intuit.com/questions/1894477-why-is-my-federal-refund-less-than-i-expected