Labour law

just file the application for recovery of your money in the laboour court ,if you still think your problem would be solved by issuing a notice just mention the facts and how the money come due,in the last give some time to release the money or face the consequentail legal action in the court of law, start with " Without Prejudice to any of my rights 

Or simply consult lawyer and ask him for issunace of notice that would sense more legal.