3G doesn't work on apple iphone 4?

I took a Tata docomo Rs.250 3G plan and when reached home and switched on 3G from general it don't work. I went to the showroom for setting the person gave the setting but on 2g songs is coming instead of 3g

Yes i have faced same problem! The problem is with the network, docomo does not have 3g in few states but the recharge happens or you have to change your 2g 3g settings in your i phone