Product: Debt collection

Start to receive multiple phone calls leaving messages that a law suit is being filed against me by XXXX XXXX   that day. Called back. Was told I was served documents ( which I was not ). regarding a debt I owed. I asked who it is that is trying to collect. Was told ACE check services. I explained this was already taken care of years ago. 
I was told they are filing a law suit regardless. 
Calls continued. Today got a call from a private number asking for an individual not at this number. Same person called back then asking for that person and myself. I asked who it is. They said they are a process sever and are ready to serve me legal documents today that have been filed against me in Court. I needed to call this number from a law firm to avoid legal actions. I asked what Court & who the other person was they mentioned. They hung up. 
I called that number. I was told as of XXXX XXXX  today they will file against me and levy my bank account and I will no longer be able to use my bank card or account from then on up unless I pay my debt today. I asked which Court it is being filed at. I was told that they do not know as they are in XXXX, AZ. I explained so am I & thats why I was asking. He said your local Court. I again asked what Court. He said he couldn't tell me and I would find out soon enough. I asked further questions in regards to this debt. I explained there is no debt owed as I made the payments that were asked of me & it was settled. He said I did not and that my bank returned payments. I said no way. He said well you are out off luck then there are no further notes on here & you only made 3 payments. I stated I already told them before that these 3 payments settled the original debt. He said if I do not pay today a lot of addt cost will be added. I explained I am fully XXXX & I have no extra money. The debt was settled long ago. I stated I would like more info on the process server and their Company. I was hung up on. I called them back & again was hung up on. After that every time it went to VM. I left a message stating that I would have liked to work something out and that hanging up on someone isnt a solution. It is rude. That I am sure I will be able to find who their supervisor is. Actually checked online. There is no such Company. I called them back left another message letting them know that I am fully XXXX as such they cant levy against my acct as Social Security Payments are exempt. I called back one more time, again answering machine. I told them I will need proof of my debt as they are NOT a law office and to claim so is illegal. I further stated I expect proof of my debt to be send to me within 5 business days as well as any legal paperwork that has been filed. I made them aware that I have USPS informed delivery. So they cant claim they send it if they did not. 
I then looked at the other number that had originally contacted me. Same number ( except last 2 digits ) but the message they had left me states a diff company. After more research found out that a class action has been filed against them in a diff state for deceptive collections. I agree. Stating you are a process server and that you are a law firm when in fact you are a collection agency is deceptive. Stating that I wont be able to use either my bank card or my account when no lawsuit has been filed or even won as of yet is further deceptive. 
If you need their names, phone numbers or voice mails I gladly forward them to you.