Is the amount sent/issued by the IRS the same as the refund amount shown on your federal tax return Form 1040 Line 35a? - https://www.irs.gov/refunds
If not, then go to this IRS website for information on reduced refunds - https://www.irs.gov/taxtopics/tc203
Are you also receiving a state tax refund? If so, the state refund is sent directly to you based on how you chose to receive the state tax refund.
Use this TurboTax support FAQ to check the state tax refund status - https://ttlc.intuit.com/questions/1899433-how-do-i-track-my-state-refund
