Per the IRS website What to expect for Refunds This Year: The IRS issues more than 9 out of 10 refunds in less than 21 days after a return has been accepted. However, it’s possible your tax return may require additional review and take longer. Where’s My Refund? has the most up to date information available about your refund. The tool is updated daily (usually in the overnight hours) so you don’t need to check more often.
Please note, if you claimed the Earned Income Tax Credit (EITC) or the Additional Child Tax Credit (ACTC) this could be why you're seeing a delay.
Please see the TurboTax FAQ: Some 2019 federal refunds are delayed due to the PATH Act for more information.