Maryland State refund from turbo tax wrong

[chris B22]

I filed my taxes with Turbo Tax and it said my state refund was about $1,400. In the beginning of June, I got a letter from State of Maryland titled "Personal Income Tax Computation Notice". It had all my tax information and the same figures I inputted into turbo tax. The only difference was it said my tax refund was about $2,650, and there was a check for the difference. I even went over my State tax form and followed all the instructions online as if I was filling my taxes out by hand. I ended up with the same figure (2,650). My question is how did turbo tax get it so wrong. It was almost a difference of $1,200, when the numbers and information were all exactly the same. This definitely makes me question how reliable turbo tax is, and thankful the state actually took care of it themselves and sent me the right amount. 

[xmasbaby0]

No one else can see your tax return or what you entered into the software.  So we can only try to guess.

Did you receive unemployment with state tax withheld?   Did you file your tax return before the tax laws changed that waived federal tax on the first $10200 of unemployment and before your state also changed its laws to go along with that same waiver in regard to unemployment?

[chris B22]

No, nothing like that. My taxes are fairly straight forward. Standard deductions along with Earned income tax credit. Everything lined up between turbo tax, letter of summary from Maryland, and doing it by hand until it came to the refundable amount from the Earned Income Credit.  It was just off by a significant amount and i've dug through my original state taxes I filed through Turbo Tax but there isn't really any explanation it just refers to the official Maryland State taxes instructions which I did on my own and I get the same number in the letter the State of Maryland sent me. I don't mind posting the specific figures ( maryland tax after standard deduction, Earned Income Credit, and then the refundable amount), because to me it makes no sense.