Your taxes withheld ($310) are different from your tax assessed.
Your employer withholds taxes according to state withholding tables that estimates (sometimes well and sometimes not so well) the amount of tax that you might owe.
But, of course, the withholding tables don't know the particulars of your actual tax situation.
At the end of the year, you calculate (with TurboTax's help) your actual tax assessed. Then the withholding is subtracted from your assessed taxes to give you the tax due number.
In your case, you were assessed $892 in tax, of which only $310 was available to apply to it.