Product: Debt collection

several months ago my step son told me his mother received a call from a debt collector for me. thats all the info I had. I did nothing. two days ago, my daughter, who is married with a different last name got a text addressed to me asking I call XXXX re acct # XXXX. No other info. I called the number and asked right away what it was about. the woman said they were not a debt collector but were trying to collect a debt. I asked for who and she wouldn't tell me. She started going off on all this legal info and I asked several times before she told me any more that I wantedt ot know who the creditor was. she put me on hold to go talk to a supervisor. I hung up. She called me back from XXXX. She said we were disconnected and i told her no, i hung up bc if she is not willing to give me any info on the creditor I was not interested in hearing any more. she told me i would not be disrespectful to her or talk to her like that. I hung up. I then did a number search on both numbers and the best I came up with is that it was a scam. no infor on those numbers came up. I got a text message today from XXXX asking for me to call re the same acct number. I called. I was then told that the debt was from XXXX for staples. but that it has been charged off in XXXX I asked what the name of the company was that was actually calling me and was told it was XXXX XXXX but that they are not debt collectors, they are the ones who will file a law suit against me if I do not pay. If I agree to pay they will let me pay {$700.00}. but if they sue me it will most likely be for about XXXX or XXXX dollars. she said they will serve me papers. I said well, I haven't heard anything from anyone for 13 years. if they know how to serve me at my current address why would then not try to send me letters to try to collect. she said it was not their job to find me only to serve me if they want to sue me and that if I don't pay they will garnish my wages and have my bank accounts frozen. I trold her I was on a fixed income bc I am XXXX and receive ssdi and I didn't think they could garnish that or freeze my accounts and she said oh yes they can and they will. she asked if I wanted to talk to the? mediation dept? I said yes. I was then threatened again that I needed to give my email address bc they dfo n't do anything by regular mail and that I needed to agree to pay today. she then asked for my credit card numbe I would be paying with and I said, wait, I have no idea if this is even real and you want me to just give you a debit or cc number? no, I am not doing that. I want documentation sent to my home vial mail. she said we do not do that. You can either pay {$700.00} & change today by XXXX or you will be sued. she said she couldn't email me the documents UNLESS MY DEBIT OR CC NUMBER WAS GIVEN. I refused. Then I said, I moved several times, each time I put in a change of address, if they were in fact trying to getr in touch with me, I would have gotten mail forwarded to me. I was at the address they had on file for 3 years before I moved and the next house I was at for 3 years and not once did they send me anyrthing. she said, its not their responsibility to find you. and I told her, well you have my current address now and you rigfht away go to suing me? I ended the call. I then did a search and I read that ssi & ssdi payments for XXXX can not be garnished and that the statute of limitations in MA is 6 years. They charged this acct off in XXXX  I feel this is a last ditch effort to collect on a debt that I CONTESTED in the first place because it was for a defective computer that they refused to let me return and refused for 3 years to fix. Now they are threatening to freeze my bank and sue me and were very nasty on the phone and yes, I got nasty back bc I felt threatened. This is wrong and I feel illegal. I know if they continue to contact me more than once a week that is illegal as well and I will continue to file complaints until they stop. I am still unable to find any information on any of the phone numbers that were used to contact me. I dont even know who or what this XXXX XXXX XXXX is. I only know I did get an email and I will not open it because I really don't know if this is a scam or not. this debt doesn't even show up on my credit report.