GSCM Collection Department fake debt collection notice Carson City Nevada

I received an "Urgent Notice: Debt Collection" notice stating that I owed $39.97, and if I didn't pay by 7/7/2014 the collection fee would be added and a total of $59.97 will be due.  I tried calling the only number listed on the notice 1-818-565-8870 which is completely automated.  I tried pressing 0 and # to get a human on the phone which resulted in the call being terminated.  I tried calling the number again, but now I get a message that the number has been disconnected!  I have not received any product for which I would owe the original $39.97, and this was the first ever notice received.  It is also suspicious that the letter is dated 6/7/2014, but I did not receive it until 6/30/2014. I will be sending a certified letter to the payment address indicating that I am disputing the charge and will report back to this site if they actually follow up with anything.