Product: Student loan

My son contracted with XXXX ( now Navient ) for student loans. The first loan was originated on XXXX/XXXX/XXXX for the amount of {$10000.00}, and the second loan was originated on XXXX/XXXX/XXXX for the amount of {$15000.00}. I cosigned for the student loans at that time. I believe that XXXX ( now Navient ) and XXXX XXXX XXXX College ( XXXX XXXX, Kansas ) conspired in predatory lending practices in order to persuade college students, including my son, to take out high dollar loans at excessive interest rates and unfavorable terms. At the time, the school and lending agency did not offer any other alternatives, and insisted that this was the only available loan option. Additionally, we were not given any accounting as to how the money was used. Since that time, my son has been unable to meet his payment obligations due to personal financial difficulties. He made numerous attempts to negotiate payment terms with Navient, but the company was unwilling to work with him. As a result, he defaulted on his loans, which made the loans my responsibility, as cosigner. I have been in frequent communication with Navient, but their process management is uncoordinated. As a result, I have had to deal with multiple individuals, none of whom appear to talk with each other. 

In addition, Navient 's record keeping system is unreliable. My XXXX daughters also have student loans with Navient, and Navient has confused payment information between the different loans. Navient also withdrew loan payments from my personal checking account without authorization, both for my son 's loans and for XXXX of my daughter 's loans. Navient has engaged in extensive harassment by calling me on multiple phone lines many times a day, including phone calls prior to XXXX and after XXXX, for an extended period of time. Many of these phone calls included threats and accusations, including demands that I make immediate payments using personal credit cards. In my attempts to resolve this dispute with Navient, I requested transcripts of these phone calls, which they first said they could provide, but subsequently, they claimed that such transcripts are not available. 

I have, after many attempts, been able to reach a partial verbal agreement with Navient, which stipulates the following. 
A downpayment of {$2500.00}, which I have made Monthly payments of {$160.00}, which I have been making Interest rate of 0.001 % However, I have been unable to obtain a written statement which includes the total number of payments the company will require me to make, and the total amount to pay off the loan. Since Navient has lost record of my payments in the past, and I have not been able to get an agreement in writing, I am concerned that, if the individual I have been dealing with leaves the company, I will be starting over in this process. However, the company has refused to address my request for an agreement in writing. They demand that I make monthly payments on their terms, but will not give me the information I need to set up automatic payments from my bank, and have ignored my request for a written agreement to formalize the new loan terms. I find them unresponsive and unreliable.