2020 Maryland state tax return doesn't have either standard or itemized deduction option selected?

[egk1]

I'm about to submit an amendment to my 2020 returns (both federal and state). 

In reviewing my MD state return documents from TT, I noticed that neither the standard or itemized deduction box is checked. How could that even happen?  My federal return has the standard deduction box ticked. As best as I can remember, in 2020 I answered all the prompts, and my returns were accepted. I owed no taxes.

Now I'm having trouble figuring out how to fill out the 502X without a claimed deduction. Is there a rule somewhere stating that you don't have to claim either for some reason?

[ThomasM125]

It is possible you don't have any Maryland adjusted gross income listed on line 16 of your form 502. That can happen when you have tax exempt retirement income, child care expenses, or other deductions or exemptions. In that case, you wouldn't get any deduction since you have no income to deduct from.