I see that you have never met the owner by your question. Perhaps their is a property manager that you have been in contact with. I would try to speak to the property management company and let them know that a notice came to the home and you are concerned. See if this gets you somewhere for free at least.
Of course you can go and speak with an attorney and pay a couple hundred bucks for the same information you might get free elsewhere.
The other office that you can visit for free is Hud.gov
Call make an appointment and see if you can speak with them about the situation.
The next step you can take is to call the Housing Authority in your area to see if they have some advice for free.
Finally, it appears that at some point you will need to move so I would get yourself prepared for that. I believe you have a few months depending on what type of document you received in the mail but I would just get prepared. Good luck!