Why did you get the 1099G? It could be for unemployment or a state refund you got or something else.
A State Tax Refund in box 2 is taxable if you itemized deductions on that prior year's federal return and took a deduction for state income taxes instead of the sale tax. You got a deduction benefit for it so now you have to include it as income. If you took the standard deduction it is not taxable and you don't need to report it.
