Verizon Dinged My Credit, Saying I Skipped Out On Bill I Didn't Owe

After Bill cut ties with Verizon, he says the company issued a phantom $120 charge on his American Express card. When he successfully got the charge reversed, Verizon’s collections agency hounded him, saying he still owed the money. Eventually the company wrote off the “debt,” causing Bill’s credit score to drop.

In his words:

Last year my contract with Verizon was nearing it’s end and at the time they didn’t have any smartphones that I was interested in. So, I ended my contract and signed up with T-mobile on a trial basis only, since I heard that T-mobile has service issues in NYC. I signed onto my Verizon account and made sure to pay any outstanding balances. After about 30 days I felt that T-mobile’s service was not what I wanted, so I paid my balance and switched to Sprint. I am currently with Sprint now. After several more months I was checking my Amex bill online and noticed that Verizon had charged me $120.07, so I tried to sign onto my Verizon account to see what these charges were about. However, Verizon had closed my online account. When I was with them I had paperless billing, so I didn’t have any hardcopies of any bills. That being the case I opened an inquiry with American Express. They investigated for 6 weeks and eventually found in my favor.

A few months later I received a letter from a collection agency, stating that I owed Verizon $120.07, in the letter it also stated that if I disputed the debt I should write them a letter and then they would furnish me a written copy of the charges and/or verdict against me. I wrote a letter stating that I disputed the charge and would not pay until I received something showing what these charges were and proving that I did indeed owe them something. I never heard back from them. A month or so later Verizon charged my Amex card again.

I started another inquiry and Amex again found in my favor, this time they also said that the would prevent Verizon from charging my card again. Sometime later I received another letter from a second collection agency. So I updated my initial letter and sent that to the second agency. I never heard back from them either.

Now about 2 weeks ago I received a third letter from another collection agency, and I sent them a letter as well. A week ago I received a letter from Verizon stating that this letter verified my debt (it had no details other than the account number and the amount of the “debt”), and that they are writing off my debt. I checked my credit reports which I do every month and my score had dropped 100 pts. because Verizon told them I skipped out on the debt. I wrote equifax and transunion disputing Verzion’s claim and that is where we are currently. I don’t know how to settle this. If Verizon had at any point shown me that I did have a legitimate debt I would have paid, but now I feel that my formerly excellent credit will probably be ruined. Does anyone have any helpful advice on how to resolve this?

Any advice for Bill?