First Source is a fraud

I was contacted by First Source regarding debt owed to American Express prior to my divorce. I notified them that the debt was not my responsibility and that was going to be addressed in court. They said if I paid half the debt they would clear my name and credit. I agreed since the amount was under $1000 and I had many issues with my divorce, it was one less hassle. They began taking money each month as agreed but never sent me an agreement stating that they would clear my name and credit when 1/2 the debt, which is what we mutally agreed I was responsible for, was paid. Better yet, they senyt a statement saying I was responsible for the FULL amount. I have contacted them with no luck at resolving and am now going to conact AMEX, they should not use such a fraudulent compant for their debt collection, it smears the AMEX name.