I had a similar problem once. Cleared it up by writing a letter with the entire situation, the letter started with: To: My State's Attorney General

I had a similar problem once. Cleared it up by writing a letter with the entire situation, the letter started with: To: My State's Attorney General Address.... CC: Company affecting my credit Address... CC: Collection company Address... Then made three copies and sent the letter's out. AG's office sent me a case number after just two weeks. The Company reporting the bad debt within two months, denying any wrong doing while immediately "fixing" the "misunderstanding". It was an interesting learning experience. For 75K, perhaps I should have gotten a lawyer.