Once your return is accepted, it is the IRS who determines how long it takes to process your Federal return. You may have forms in your return (like the EITC/ACTC) that can delay the processing of your return.
The IRS expects the earliest EITC/ACTC related refunds to be available in taxpayer bank accounts or debit cards starting February 27, if these taxpayers chose direct deposit and there are no other issues with their tax return.
This is normal. With the new tax laws and updates, the IRS is taking every precaution to ensure each tax returned is process correctly and fully. It can take anywhere from a few hours to 3 weeks to update. Until the IRS starts processing it on their own, you may not find record of it or the website may say that you have put in incorrect information when tracking your federal refund. As your return moves through the system, the status of it will be updated accordingly. Continue checking the Where’s My Federal Refund? tool for updates. Updates are made daily, usually overnight. You may also download the IRS2Go app to check your Federal refund status
https://ttlc.intuit.com/community/return-status/help/what-does-accepted-mean/00/26285
Note: The IRS expects to issue most refunds in less than 21 business days after being accepted. Taxpayers who claim the Earned Income Tax Credit (EITC) or the Additional Child Tax Credit (ACTC) will experience a refund hold and a delay in processing.