Independent Tv - Not responding properly

I am a customer of "independent tv set up box" from Dharwad-( Kanatak-******). A few days back we installed this setup box for a *-year subscription of Rs. ****/- from the local dealer (name: Vinay-**********). We using the service since *-* months but in starting it was good but now the service is very bad. Some channels have gone blank that shows with "contact customer care" although we contacted that toll-free no. but no use. Still, we facing very bad service and most of Kannada channels not running properly (like TV*, Uday packages all- Uday movies, Uday comedy, Uday etc also no sound). We are really fed up with the bad service. A few days back one of their technicians came to the home and repaired but he charged Rs.*** for only * mins service, before buying the service the dealer says that we have *-year free service. Then why he charged us? Is this the service they providing to customers? Really we are getting irritation from this. I want all the channels to be run clearly.