Some refunds do take longer to process than others.
https://ttlc.intuit.com/replies/3302330
The IRS Where's My Refund? website page (www.irs.gov/refunds) has a tracker that displays progress through 3 stages: (1) Return Received, (2) Refund Approved and (3) Refund Sent. Once your refund status says "Refund Sent", please allow additional time for refunds to be processed after leaving the IRS, and for financial institutions to accept and deposit them to bank accounts and products like debit cards.
My federal refund is also taking a suspiciously long time. Both our state and federal were approved January 31. We have received our state, but our federal still says pending on the IRS website. Turbotax has emailed me, informing me the charges will be coming out of my bank account instead of my refund (due to it taking over 40 days). I won't be filing with turbotax next year.
TurboTax is not connected to the IRS or state department(s) of revenue refund tracking tools. We don't receive real time updates from the IRS.
If you are concerned about the status of your taxes and you are past the 21 day mark you should call the IRS to see if they can provide you with any additional information.