Here's what I don't understand:
"I do my job only because some of people really need my help. And I never charge them."
"I never asked commission from him too. I don't need commission for my hard-working. Because the school will pay"

Then you complain that:
"But Robert Arnold Kerr never wants to pay me and ever never say thanks to me."

Why does he have to pay you? I thought the school would do that?