AES/PHEAA Student Loan Complaint

AES/PHEAA Student loan department,

Non-federal student loan Dealing with my lender or servicer Don't agree with fees charged Oklahoma

I applied for - degree and was excepted -/-/-. I decided to get a loan to help support through my 2yrs of schooling with American Education Services. I graduated -/-/- with my degree and starting working -/-/- for a -. I went to my bank and consolidated all of my debt -/-/-. My loan officer wanted the payoff for all loans or credit cards before he would give me a check. I called AES for a payoff amount and then sent them a check for the pay off amount. -/-/- AES sent a statement showing I still owed $2500.00, I called and asked why I paid you off 8 years ago. The representative said your account shows you called for a pay off but that was n't a pay off. I said I did n't understand why and after 8 years they are chasing me down for more money and that I would n't be in a big hurry to pay them anymore money. With it being 8 years later I do not have any documents other than a copy of the check I received from my bank for the consolidation. I have now been turned over to debt collections and my credit report is showing a ding. I did call AES for a master promissory letter but does n't show anything about owing more money. I do n't know where to go from here, I called for pay off -/-/- and sent a check knowing that I paid them off. Please help me in my dilemma. Thank you