Product: Debt collection

I was in the XXXX XXXX XXXX until XXXX. We were XXXX and called to XXXX XXXX @ XXXX. I purchased a cell phone and plan from XXXX XXXX XXXX  to stay in contact with my family, however after having billing issues with {$1000.00} a month in roaming charges alone. They would adjust it each cycle and remove the charges but I would have to wait for my payment to be credited. Finally disgusted with this I contacted XXXX  XXXX XXXX and explained my situation and was informed by them that being on XXXX XXXX they would cancel my contract and close my account. I never thought about it again until I received my paycheck in XX/XX/XXXX that had {$150.00} missing to garnishment on my weekly pay. My company never informed me of this and this collections company would not even speak to me. They gave me the name of their attorney Love, Beal, Nixon. I was informed by them that I owed over {$6000.00} and could not tell me who or where the original debt came from. I searched my credit report and this collections was not on my report. I called their attorney again and asked for the information and all they gave me was a judgement number. After days of searching I finally found out that the the debt was from XXXX  XXXX XXXX for the contract that was supposed to be taken care of due to my XXXX XXXX status at the time and found out that the only paperwork they served for me to appear in court to challenge this at the time was served to my father. I love my father but he doesn't speak on my behalf. I reached out to XXXX XXXX XXXX and was told they showed the account closed and settled and they didn't understand how it was in collections and we're shocked when I explained they received a {$6000.00} judgement for this. I have attempted to get all information regarding the math, charges, paperwork and legality on this matter. I have submitted this request in writing, verbally and through emails and to date I have not received any information or response. I have tried to reach out to attempt to settle. I have seen many many cases of the same issues with this company regarding fraud, misrepresentation, unprofessionalism and unwillingness to provide documentation the law requires they provide. There have been several law suits and debts overturned. I have contacted legal advice and been told since my debt is so old and changed hands it would be nearly impossible to win in court without paying more in representation then the debt cost. They have informed me I should file bankruptcy but that seems a drastic measure when I should not owe this at all. I am afraid to open my check every week worrying it will not be whole. I have filed a dispute with the company and the better business bureau. I don't understand how something that happened while I was serving my country and had safeguards in place for just this type of circumstance could be allowed to haunt me 15 years later, how charges are still being added, and this company does not feel obligated to work with me to rectify this. I was XXXX XXXX XXXX XXXX XXXX XXXX XXXX  XXXX when I signed this initial contract and still on XXXX XXXX when XXXX  XXXX XXXX agreed to cancel my contract and release me of any further obligation. I was assured this was closed under the service member protection act. Please help