Non-payment of commission

I had a commission agreement with Andrea from The Red Kitchen to sell her freshly baked goods, where I would receive 7,5% commission on each sale. She initially took weeks and weeks to pay me, after having to continually remind her that I was still waiting for payment, despite me having arranged for her to be paid almost immediately after delivery. I was extremely disappointed and surprised that after my last sale, where my commission was a mere R165, she just ignored my numerous requests for payment, eventually not responding to me at all. This kind of behaviour is completely unprofessional, ********* and unexpected. I asked her to let me know if there was a problem, but again received no acknowledgement or response.