What TurboTax shows you is just an estimate based on the fact that many refunds are issued within 21 days of the return being accepted. The IRS does not update TurboTax on the actual issue date of a specific refund. If you qualified for the Earned income credit or Additional Child Tax Credit here is more information about the PATH Act delay, but keep in mind that the IRS site for Where's my refund, https://www.irs.gov/refunds is the final authority.
https://ttlc.intuit.com/replies/5556415
If the PATH Act delay does not apply to your situation, please see the following information about contacting the IRS after the 21 day wait:
https://ttlc.intuit.com/replies/3302084