The IRS says 9 out of 10 filers who efile and choose direct deposit will get their refunds within 21 days. That still leaves a considerable number of people who do not. Some returns take longer for additional processing due to specific items in the return. Some are pulled at random for more thorough investigation.
You can double-check with this tool to be sure the return was efiled successfully and accepted:
https://shop.turbotax.intuit.com/efile/efile_status_lookup.jsp
If that showed it was accepted, you can use this IRS "Where's My Refund" tool to monitor the status:
https://www.irs.gov/Refunds
NOTE: When entering your refund amount, use only the Federal refund amount and not any total refund amount that includes a state refund. The figure is shown on your 2018 Federal Form 1040, Line 20a.
If that IRS tool shows that the refund has been sent, but you never received it, report back for more info.
If the IRS tool says it is still "being processed", then if it goes longer than 21 days, we can tell you how to speak to a live agent at the IRS.
To track a state refund:
https://ttlc.intuit.com/questions/1899433-how-do-i-track-my-state-refund
