How did you find out that you owe MD from 12 years ago? Did the state of MD send you a letter? If so, did you contact the state to make sure it is not a scam?
https://www.marylandtaxes.gov/contact-us.php
I moved to South Carolina about a year ago and I had to get my car registered. I put it off since my tags were paid for and I had to get a copy of my title from Maryland. When I called to inquire, they told me that I had a red flag That I owe taxes to the state of Maryland where I used to live. My husband passed away 2013. And this is the year that they said I owe taxes.
@Xalintsonny You will need to contact the state of MD to sort this out. TurboTax cannot find out about matters like that for you.
In general, the IRS and most states have a ten year statute of limitation when it comes to collecting back taxes. You can read more from this article from Thomson Reuters. You can reference MD Code Tax-Gen. 13-1103 if you claim the tax is not owed due to the statute of limitation expiring.