Wrong Recharge and Denying Responsibility .

I did a Internet recharge of rs. 333 on my BSNl No. 3 months ago in May through Freecharge. I confirmed the recharge value and benefits with the Operator of the BSNL. I then recharged through the Freecharge and chose the Plan from their provided Plan List. In their Plan List the 333 rs. Internet recharge was available, So I did the recharge. But What I received was Top Up. Which I did not know at that time and I went ahead and started using the Internet. My balance soon exhausted and I contacted the Operator to know why my net wasn't working and they told me that the recharge done was Top Up. Then I contacted immediately with Freecharge through Email. They totally denied their fault and blamed me that I selected the option for Top Up which isn't possible because I selected the Plan from the list where the benefits were to receive were mentioned. Since I did not had any proof I couldn't file a complaint. I kept telling them that fault was from their side but they kept denying my claims and kept blaming me. But I was right, after 3 months of my original internet plan for which I did recharge was to expire and an automated system response from their server came to me, telling me that my Internet plan was to expire. (It is Freecharge's Reminder Programme). Then I knew I had proof (The Email from there server about my recharge). Now I am seeking legal options which I can pursue to teach them a lesson and get suitable revenue for treating me bad, denying claims and fraud. Please provide me legal guidance as I have been struggling for 3 months and my requests were denied.