How do I find my 2020 Hawaii overpayment ? I filled my 2020 state tax through Turbotax, but it said it didn't see a taxable state refund on my federal tax return

Your 2020 Form N-11, Individual Income Tax Return Line 42 shows the amount overpaid. 

Your State refund is not taxable unless all three of the following are true:

• You itemized deductions last year, instead of taking the standard deduction
• You claimed state and local income taxes (not general sales taxes)
• Claiming the deduction helped you increase your federal refund or lower your tax bill

For more information please check Do I need to report the state or local refund I got last year? Is it taxable?