It can take anywhere from a few days to 3 weeks to go from acceptance to approval. If it has been longer than 21 days, then you may want to take this link below into consideration. https://ttlc.intuit.com/replies/3302084

Also, Taxpayers who claim the Earned Income Tax Credit or the Additional Child Tax Credit may experience a refund hold.  According to the Protecting Americans from Tax Hikes (PATH) Act, the IRS cannot issue these refunds before mid-February. The IRS expects the earliest EITC/ACTC related refunds to be available in taxpayer bank accounts or debit cards starting February 27, 2018, if these taxpayers chose direct deposit and there are no other issues with their tax return.