I filed an amended tax return through TurboTax and was expected a large refund. The IRS refunded a much smaller amount. How was TurboTax so wrong?

[xmasbaby0]

No one can see your account or your return, so we do not know what you changed or when you did it.  It is taking six months or more for the IRS to process amended returns.  We do not/cannot know if the IRS processed your Form 1040X or if you simply received an extra automatic refund for unemployment or the premium tax credit, or a "plus up" stimulus payment.

When did you amend your tax return--and what did you change when you amended?

[Taxyturns3]

TurboTax advised me to amend my tax return due to the unemployment changes after we had already received our initial refund.  The Amended tax form was filed with a refund difference of $1278.  My Amendment has been adjusted by the IRS and they sent a CP21B with a refund of $394.  Big difference and am wondering why.  TurboTax has never been wrong before.

[xmasbaby0]

https://www.irs.gov/individuals/understanding-your-cp21b-notice

[Mike9241]

TurboTax advised me to amend my tax return due to the unemployment changes after we had already received our initial refund. 

Big mistake on the part of Turbotax because the IRS did not want amended returns if the only thing affected was the taxable portion of UC.  An amended return would be required if certain credits were not claimed at all on the original return and you now qualify for them or if you used the standard deduction but after the UC exemption itemizing deductions would produce an additional tax benefit.

The Amended tax form was filed with a refund difference of $1278. My Amendment has been adjusted by the IRS and they sent a CP21B with a refund of $394. Big difference and am wondering why. TurboTax has never been wrong before.

what the IRS says about the notice

Read your notice carefully to see what we changed.
Contact us if you disagree with the changes we made. is there a phone number on the notice?
Correct the copy of your tax return that you kept for your records.
Be sure to report any interest we paid you on your tax return for this year.

What if I haven't gotten answers after contacting IRS?
Call the Taxpayer Advocate at 877-777-4778​ or for TTY/TDD 800-829-4059​.