Product: Debt collection

I write to file a complaint against NAVIENT and a possible collection Scam by TWO Debt Collection companies that are BOTH contacting me for the SAME DEBT. 

Sallie Mae was the Lender for my Student Loan. 
My payment history has always been outstanding over the years. I never missed a payment. When my financial situation dropped, due to the Italian economical crisis and later on, by my separation, I found myself becoming a single mom of a XXXX years old baby and it all became very hard on my finances. That didnt stop me from trying to still make payments on Sallie Maes Loan. I could not work full time anymore with the baby and as a single mom, so I requested my Lenders to lower my payments. 
When my Loan went from Sallie Mae to Navient, thats when the problems began.

When my financial situation became unbearable, I tried all avenues to work with my Loan holders but the result was a complete absence of acknowledgement of my situation in a completely unprofessional manner. My Loan Holders pretended never to have received the numerous letters and e-mails I sent ( I kept all copies of them on file ). I was approved for an Income Driven Repayment Plan the year before and all they had to do was to re-approve for the new year plan. 
In my last communications I came to the point to even exhort them to look at my financial situation. They were sent all the papers that showed my income and my financial struggle in having to make full payments. 
I had every right to request a lower payment and a lower percentage based on my income. I already had all the papers approved the preceding year and it was just matter of them renewing with a signature for the new year that would allow me the continuation of lower payments into the following year. It was not a request. Just a simple renewal! They only had to review my tax return to confirm that my situation hadnt changed. They pretended not to receive my papers and made the due date pass. They pretended not to receive any of my communications. I wrote to them and sent my papers to them 5 times. I called them and let them know that everything had been sent in. Their following action was : they made the due date pass so that they could proceed in sending me a request of a payment in full. It was transparent that their entire action was deliberately taken to this path. I then wrote a certified final e-mail to them so I could have profs of validity in court if needed and they never replied to it. 
At that time I did not absolutely know how to handle this case anymore. I even wrote to them that the anxiety and psychological pressure they were putting on me by not acknowledging my letters and forms sent in was unbearable and was getting me sick. I did not have finances to hire a lawyer. From overseas it is hard to find solutions as well. 
Only now I come to know that Navient has committed numerous infractions like these and has been sued by numerous students for their illicit actions. 

Now, because of their unethical conduct, I find myself paying the consequences of an escalated outcome. 
I was contacted by not one but two Debt Collectors companies requesting me to pay an immense sum on a Student Loan for which I do not recognize the amount nor the Lenders Name. Both companies are contacting me on the SAME DEFICIENT LOAN SUM. The sum corresponds in no way to the amount of my Loan and the Lender is under a name I do not recognize.

I understand that all my effort in paying off my original Loan amount has for sure been completely destroyed by interests and fees. But this amount is double what I own.

And how can such request come from two companies at the same time? 

Im probably the subject of a Scam Ive sent a validation request to the first company listed as XXXX XXXX XXXX XXXX, XXXX. XXXX  XXXX, XXXX, NY XXXX and Im in process of sending a validation request to the second company listed as XXXX XXXX XXXX, XXXX XXXX XXXX, XXXX, Ma XXXX but with a letter that came not from this address but from the following : XXXX  XXXX, XXXX XXXXXXXX, XXXX, Ca XXXX which address I looked up online and it is being listed as a scam company. 
These are some links https : XXXX https : XXXX Im absolutely freighted from having to deal with such a situation. I have no idea if these companies are real or fake or if a Lender has sold a debt to both of them.

I do not absolutely want to release my personal information to any of these two Companies until Im absolutely sure they are legitimate. 
I also find it completely absurd that I have to pay for the illicit actions of my Lender if the debt comes out to really be the one I own but with a doubled amount.

Please Let me know how I should proceed from this point.

I will file a complaint with the CFPB, State Attorney General, State Department of Education, Federal Trade Commission and try to take all the steps necessary to resolve the issue. 
I would be pleased to receive any input on how to proceed on this matter. 
Sincerely