can a lawyer hold an agreement for lack of payment

I hired a lawyer and informed him after the initial payment I couldn't pay him until my license was reinstated and I could go back to work. The case took approx 6-7 months and I was never sent a bill nor asked for money. 2 days before we settled the case he informed me that if I didn't pay him the full amount of the bill he wouldn't submit the agreement. Can he do that? Now I can't teach and I am having trouble finding work. If he would have told me this in the beginning I wouldn't have hired him.