Fraudulent Account Activity - Need Direct Message Support to reach Collections

I have spoken with Nicki on the phone, who acknowledged that a second account was mistakenly or fraudulently opened for my address and auto-billed for months, despite never having any equipment associated with this new account or any services used. She could not resolve, because the account was canceled and there is an amount still "due" that was sent to collections. She told me to reach Collections at [Edited: "Personal Information"], but that number only plays a message that the office is closed. A person from Collections named Carly had previously reached out with a number, [Edited: "Personal Information"], that is perpetually busy. 

HOW DO I REACH COLLECTIONS? This is a nightmarish Catch-22 that I have wasted hours and hours on. I really should be refunded the $328.21 that remained billed to my credit card after I reported fraud. I'd be happy now just to get the collection action dismissed.