IRS changed my taxes after my return was accepted and reduced my refund. It seems they applied a refundable credit before the non-refundable credit. Can they do this?

[meldiguette-gmai]

Carry over adoption tax credit was not applied as child tax credit (3 dependents..so $6000) of which $4500 is refundable was applied first and brought tax liability to zero.  

[JulieS]

Yes, tax credits are applied to your tax return in the same order they are listed on Form 1040:

1. Child Tax Credit and Other Dependent Credit.
2. Other non-refundable credits, including Adoption Credit.
3. Refundable credits. 

If you did your return using TurboTax and you get a letter from the IRS, you can use the Audit Support Center as a resource. Click here for more information.