How can I dial A DSN # in the USA from a DSN phone in Iraq?

I'm currently in Iraq and I was given a morale number to call stateside. All I have to do is dial this number and I will get connected to an army base close to where I live so i can make a call home. but it isn't even allowing me to dial the whole number, and I keep getting a message saying that the call can't be completed. Is there something I'm missing.