charged service tax on entire bill

On 06th July 2014,at around 9 pm ,we have ordered some items in Pizza Hut,lake city mall,Udaipur.When we received bill,we were surprised to see that the service tax was calculated on the entire bill amount though it is supposed to be calculated on service charges only.We represented it there itself with the staff but to their rudeness,they told you can pl go ahead filing a complaint with consumer court. so we paid the bill with Inv no-14314010636 dt 06th jul 2014.

Pl help us and also other consumers who are being cheated by Pizza hut.

Regards,
Charoo MaN