My tax was efiled and accepted on 2/12/21. It is now 3/16/21 and I have yet to receive my refund. What is going on?

The Where's My Refund does not show me anything just "your refund is being processed." I spoke to someone at the IRS on 3/5/21 and they said that they were busy and I would have my refund in 4 to 6 days. Why!?