Once your return has been accepted, please give time to process a backlog of returns. They will notify you when yours is received and being processed.
Also, please keep in mind if you have an Earned Income Tax Credit and/or an Additional Child Tax Credit the earliest you can get your refund is late February.
If it's been longer than 21 days, and you don't have EIC or ACTC, please contact the IRS directly.
Please refer to the article below.
What if my IRS refund is taking longer than 21 day