If you have two children that make you eligible for the 3,000 each, so 6,000 total, you should have received half, which would have been 3,000.
If you are eligible for a 6,000 credit and you received 3,000 in advance payments, that could result in a 3,000 increase in your refund.
You might look over your 1040 to see if that is what happened.
TO LOOK AT YOUR 1040 USING TURBOTAX ONLINE:
Click "Tax Tools" on the LEFT SIDE BAR then click "Tools" which shows open below
Click "View Tax Summary" on the screen
Click "Preview my 1040" which now appears on the LEFT SIDE BAR
Refundable Child Tax Credit is on the 1040 Line 28
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