can they get away with this

In March of 2001 I started receiving invoices with past due amounts from Cellular One. After contacting them I had to fax copies of cancelled checks showing payment had been made. (I have all invoices and cancelled checks attached to them for the past 2 years.) I still received these past due balances and again had to fax the same cancelled checks. I called these people monthly to get this straight and had to repeat the story every time.The supervisors mostly were very rude and I was told that everyone makes mistakes. I have yet to receive an apology. After faxing my cancelled checks twice I finally thought things were right. However in November I was going to refinance my home while interest rates were very low. When the bank received my credit report(which was perfect except for 2 late payments on a credit card) I found I had been turned over to a collection agency and was told by the bank that if I would pay the collection agency they would approve my loan. Which I refused to do since I didnt owe them. Finally in December the collection agency told me they had received a letter from Cellular One and was taken from their list and they in turn would send a letter to the credit bureau. I lost a 5.20 rate due to Cellular One and luckily still managed to get a 6.80. Do you realize how much money this cost me?
My question is can they be held responsible?
I'm in Georgia and recently learned they had been bought by Verizon Wireless.

If you have documented proof of your claim, you can sue Cellular One for violating the Fair Credit Reporting Act.