Product: Debt collection

This statement will a sort of addendum to my original complaint number XXXX.I filed this addendum with my feedback but realized that the addendum would not be acknowledge.First I want to ad something that I failed to ask about in my original complaint and that has to do with all of the money I paid on these accounts before they went into default.By the time the accounts had gone into default I had already paid approximately {$6000.00} but that money has never been accounted for.During the many conversations I had with collection agents form the various collection agencies between XX/XX/XXXX and early XX/XX/XXXX I would inquire about that money and I was always told that I would be receiving and update and accounting for that money but it never happened.Now to move forward.Basically I am still confused about what id going on with my accounts and I am becoming increasingly fearful that I will be vulnerable to whatever power the assigned collection agency has in collecting their money.I have never tried to escape my responsibility but I am being placed in a position that I should not have been placed in.When I set up my payment agreement with the first collection agency in XX/XX/XXXX I had every intention of faithfully sticking with that agreement but the collection agencies have continued to complicate this matter by changing agencies and losing my account.From XX/XX/XXXX to XX/XX/XXXX I never missed a payment.Then in XX/XX/XXXX my XX/XX/XXXX payment was returned to me which set off a whole set of negative events which I explained in my original complaint.Then during the first week of XX/XX/XXXX I received a phone call from a person who identified himself as a XXXX XXXX  representing a collection agency called " Navient '' .His telephone number is XXXX-Ext,XXXX.XXXX and I had a 30 minute conversation explaining what had happened during the history of my accounts and why whatever happened, happened.He explained that he was still in the middle of his research and would probably be finished sometime during the third week of XX/XX/XXXX.I asked him if I should go ahead and send in my XX/XX/XXXX payment which I normally sent in between the XX/XX/XXXX and the XX/XX/XXXX of each month and he suggested that I should.He told me that he would be calling me as soon as he concluded his investigation.XXXX concluded our conversation with an invitation to call him if I had any other questions.Astonshingly, the very next day my XX/XX/XXXX check had been returned to me.I of course called XXXX and left a voice message.I called XXXX a couple more times but he never returned my calls.Around or about XX/XX/XXXX to XX/XX/XXXX I received two letters from a company called XXXX, XXXX XXXX XXXX XXXX XXXX XXXX.Interestingly this is one of the collection agencies I was referred to back in XX/XX/XXXX when I was trying to find out what was going on with my accounts when my first check was returned.I was told by a representative that she could not talk to be because I " live in Arizona '' .I called this company and I was told by an operator that they indeed have my accounts and that my account manager was being managed by a person named " XXXX '' .She said that she would notify XXXX to call me the same day but he did not.I called and left messages for XXXX on four subsequent calls but he has never called me back, Their records should show that I did call. 

So at this point I am completely lost and I do not know where to turn.I just do n't want them to after me because of their inefficiency and mistakes in handling my accounts. 

Please help. 
XXXX XXXX