This was happened in 2014. Worst experience ever. They provided me incomplete info which said 500 mb free wid a no. Which I dialled to get further details but that led to reduction of 125rs from my balance and my old data of 1000mb 3g leaving me with 500 mb 2g data.
When I discussed the problem with customer care service they denied to give my money back nd also retrive my old plan.many times they charge rs3 or rs20 for various stuff which I dont know or have asked for.