There was an outstanding balance owed by my ex-wife at a dentist for our children. The dentist forwarded the debt to a debt collector in XX/XX/XXXX and when I was contacted I immediately payed the debt. In XX/XX/XXXX the debt collector added a collection to my credit report for {$720.00} and refuses to remove it. I contacted the dentist office and they report they have not received the money I paid to the debt collector. Also the balance was only {$470.00} yet I paid {$610.00}. The dentist office was supposed to take care of this error but they refuse to answer my phone calls and the debt collector hangs up on me.