Hera are your options.1) Go to the local MTNL office. Talk cleverly not rudely and tell them that if they charge you for your downloads you will take it up with the higher authorities. Check in the forum for for the GM number. Keep it handy with you in case you need it.2) Tell them to convert your plan to the recent night unlimited one if its already not done. 3) In case you are going to bite them , bite them hard. Make sure they realize their mistake. MTNL is a good internet service but the sarkari babus are a shit to deal with.