Previous Homeowner Is Refusing To Pay Business Tax, State Is Threatening To Put A Lien On My House

Location: Oregon

I purchased a home in 2019 from a husband/wife couple. They moved to a different neighborhood in the same city.

The husband works a standard office job. The wife has / had a sole proprietor LLC that was registered to the home that they sold and I now own.

She left her phone number, and for the first year, I would arrange for her to come by to pick up her mail, and told her multiple times that she should update her address and put in a mail forwarding request with the post office. She did not, so I stopped arranging mail pick-ups, hoping she would get the hint. She did not.

Around the 2-year mark, a letter came from the state tax office. I didn't check the address and accidentally opened it, thinking I had an issue with my returns. Come to find out that her LLC owes taxes and is accruing penalties.

I texted her to let her know about this, and got a "Thanks, I'll take care of it!". She did not, and the letters kept coming. I have tried "return to sender, no longer at address" at least a dozen times. At one point, I wrote to the tax office, with copies of the sale documents and her public business info showing the same name. The letters keep coming.

Now we are nearly 7 years after the sale, and the state sent a much thicker envelope than usual. Opened it out of curiousity (technically illegal, whatever), and the state is threatening to put a lien on my house for thousands of unpaid taxes and penalties for a business I have nothing to do with. It's a "pay or else" letter, but its only a matter of time until the "or else" part.

So, now what? Is there anyone else I can contact to clear this up without involving a lawyer? I've tried everything I can think of to resolve this simply. If I hire a lawyer, will I be able to recoup that expense in a lawsuit? Who would a lawyer even be sending letters to in this scenario?

Thanks.