Robinson, Reagan & Young P.L.L.C Impossible to speak with account rep Nashville, Tennessee

I received a letter from a law firm about a collections issue that I have never heard about previous to this.  The letter said that I owed this money for a collections account and they asked me to contact them within 30 days.  

Due to an oversight, I didn't see the letter until 20 days after it was received but I tried to call as soon as I noticed and read the letter and left a message with all my account information.  I received no return call the following day and called again the second day.  Sent back to the voice mailbox.  That was last Friday.  Today, Monday, I decided to call early in the day, 8:20 am.  I got the same message.  So I looked up the company in Google and got a different number for them, which I called.  I explained my situation and she put me on hold and then in a queue. After waiting a while, I got a message that said, "Sorry but the user's mailbox can't accept more messages. Goodbye' and hung up.  I called a second time and told them that I needed to talk to a live person, telling her the message I just received.  

I called a third time and calmly and straightforwardly told her what I just heard AGAIN, and that I had checked the BBB and would put in a complaint, gave my number again and told them to call me because I would NOT be calling again.  I will follow up with a letter to them, putting my experience in writing.