Is it a crime under IPC 420?

I am using a prepaid mobile connection of a Indian company. I opted a STD voice plan for 45 days about 3 months ago (The amount was deducted from my prepaid a/c balance and I got a massage for the same; which is still saved in my inbox); but after 28 days that plan was expired without any notice and I continued to make STD calls as I didn't have any idea that plan was expired. Now when I came to know I lodged a complaint at customer care through e-mail with screen shots of that massage but after a long conversation customer care as well as appellee authority has rejected my complaint. Now I want to know; what should I do now? If I go to consumer court then mobile company will not get the proper lesson as this is the matter of less than Rs 100/- only; so they will not be fined more than a couple of hundred Rs. And if I go to the criminal court under IPC 420 I have to spend a lot of money as well as time and only God knows if they go to high court or supreme court I am not so much financially strong that I can hire a lawyer there. I want to know will these company loot customers like me without any fear? And we have no choice but just keep silence? Please advice me so I can teach them a lesson.