My federal tax return was accepted on 2-12-21 but I have not received my refund yet. How do I find out why they will not process my return.?

Is there a child credit in your return? If so, that takes longer to receive the return since the child credit is being taken care of by another dept.

If it shows ''in process'', that means that only the IRS knows what the delay is, unfortunately.   They are reviewing something on your return, but that something could be anything.  You can either try contacting them or wait for correspondence that will arrive by US mail.  

Tax Season Refund Frequently Asked Questions - Link lists possible reasons for the delay.

Here is a link to a thread that details how to go through the automated phone prompts to reach a live representative.  The steps may save you some frustration.   You can also search for a local IRS office in your area.  It may be easier to contact a local representative than using the main phone number.    You can use the ''make an appointment'' option even if you have no intention of going to the office, but that may get you a live person on the phone that can provide you some info.   They have access to the same information.