Product: Mortgage

Out of the blue this past Tuesday, XX/XX/XXXX,  I received a certified letter from a company I never heard of before (Specialized Loan Servicing) saying I was past due on my 2nd mortgage payments and I was going to be foreclosed on if I did not pay them past due payments in the amount of $XXXX.  The letter from them stated that this was the result of not having paid the initial payments dating XX/XX/XXXX and any payments since. I have no idea what they are talking about. I supposedly did not make any payments to a company I have never heard from over nine years ago and now, out of the blue, I get a letter saying I have 33 days to pay $XXXX to  bring the account up to date or they will start an accelerated foreclosure on me? I have never even heard of this company before I received this certified letter from them in the mail on XX/XX/XXXX
Previously, in XXXX  I had a second mortgage but that got rolled into my first mortgage after a fiasco with XXXX XXXX XXXX in XXXX  where they said they did not have a required signature on some paperwork from the previous mortgage holder, XXXX...even though I had a copy of it showing the signature. I ended up having to get my then-congressman XXXX  XXXX   involved to straighten it out and my mortgage that was then transferred to XXXX. The 2nd mortgage was ‘rolled’ into the first mortgage.  I no longer had a second mortgage and certainly have never heard of this company before receiving the certified letter from them on XX/XX/XXXX.
I called Specialized Loan Servicing on the day I received the certified letter and they didn't have any contact phone numbers at all for me (I've had the same land and cell phone numbers for the past 25 years)-I did give them my cell phone number. They didn't ask for my social security-which I wouldn't have given them anyway as it seemed very suspicious.  I told them I don't have a second mortgage and even if I did, why wait almost 10 years to contact me and give me only 33 days to catch up. I also brought up that I had to go through bankruptcy (unfortunately, due medical bills from a bad car accident) in XXXX  and this company and debt was not listed. The woman I talked to said she didn't know; my only options were to either pay up by XX/XX/XXXX or go through foreclosure. There was no one else or no other department or person I could talk to or escalate this to to get more information. She said there was a program I could try applying for but it was probably too late. I asked her to send me the paperwork anyway. She asked for my address, I asked her shouldn't she have this?...but gave it anyway. She started telling me just a minute, and uh-oh and then the line went dead. She did not call me back and I was not going to call her at this point until I contacted my ‘real’ mortgage company. 
I then called my current, 'real' mortgage company, XXXX, and they said that they didn't know anything about a second mortgage, the person called their manager over to talk with them and they told me it sounds like a scam, there is no second mortgage listed. They told me not to talk with them or send any money to them and to contact my state attorney general’s office.
I contacted the attorney general of MN and they said the same thing-don't call or contact them and do not send them any money; they'd never heard of a company waiting almost ten years to contact someone about late mortgage payments and told me to file an official complaint, which I have done.
Despite the person I spoke with at Specialized Loan Servicing saying they were going to send some paperwork out to me, it is XX/XX/XXXX and I have yet to receive any paperwork from Specialized Loan Servicing.
I am XXXX  years old and on XXXX. The stress from this has greatly exacerbated the condition I am on XXXX  for. I have no relatives, family or friends that can help me financially. I live with my XXXX-year-old brother, that I am guardian to (he has XXXX  and XXXX  XXXX) and keeping our home is the most important thing in the world to us. I have never missed a payment on my ‘real’ mortgage.
Who are these people?  Have you ever heard of such a thing? How or why would I make payments on a mortgage I don't have to a company I have never heard of or from before? What can I do?  Please help me! I am contacting everyone I can think of to get help on this matter and my next step it to bring it to the media's attention.