What can be done about my wage shortage?

I am an 18 year old college student and i work in a tanning salon in Knightdale, North Carolina. Recently I got paid for 49 hours and 30 minutes however, i worked 49 hours and 50 minutes. After noticing this mistake, I began to check over all of my previous checks and noticed that every one of my checks for the past 9 months have been wrong; I have been shorted. I have brought this to the attention of both my manager as well as the owner however, both of them refuse to fix the error. What can be done to result in me getting paid the difference and to stop this from continuing?