United Online Collection Division / statement showing premium owed in the amt of $19.90

I received a letter from United Online Collection Division that my account has been placed in our office for collection in the amount of $19.90 and to pay in full by November 24, 2008. My account has been closed sinse January 2008. I tried contacting the toll free number of [protected] and all I got was a recording and I did not have the option of of talking with a representative, which is very unusual. Then I decided to do some research online and discoverd this company was basically a SCAM.