I was a sales representative in North Carolina, we were paid 6% of all sales once the customer has paid their invoice. I have been terminated from my position. No where in the Handbook does it say that you will not be paid commissions upon termination.. I

I was a sales representative in North Carolina, we were paid 6% of all sales once the customer has paid their invoice. I have been terminated from my position. No where in the Handbook does it say that you will not be paid commissions upon termination.. It doesn't mention commissions at all. The sales position was created when I started working there. My employer answered me via email stating that typically an employee is not paid residual commissions upon termination, and admits it is not in the handbook. Is there anything I can do?