Attempts to collect debt not owed: Debt collection

I dispute the collection balance being reported. I had payment arrangements in place with the original creditor and made multiple attempts to resolve the account. The balance reported to collections does not appear to be accurate, and I was not provided with a clear itemized explanation showing how the amount was calculated. I made good-faith efforts to address the account, but the matter was not resolved as promised. I am requesting a full investigation and documentation supporting the reported balance, as well as a review of the information being furnished to the credit bureaus.