Service tax on advance payment

Jagjit Singh (IT and Software services)   (26 Points)

22 September 2016  

I am working with domestic Indian companies. The company paid me Advance for the IT Software services. but did not pay service tax on advance amount and also deducted TDS on the advance amount paid. 

Is this correct?

There are 3 milestones

1. advance

2 Milestone 1

3. Milestone 2

I want to understand how many invoices I have to raise to them in Total and how to apply service tax on each invoice.