I have an Iphone 4 and subscribe to Aircel 3G plan. I'm from Chennai.
I was in Bangalore this month. If my roaming carrier is selected to any other carrier other than Aircel, my phone was not connecting to Internet. I was able to make / receive calls, send SMS even when I was connected through other carriers. Where there were poor Aircel signals, if the phone chose Airtel or Vodafone, etc. I got a message that I'm "Not subscribed to Data Plans." However, when I chose Aircel manually and connected, I was able to access Internet.
From Bangalore, I went to Thiruvananthapuram. In Kerala, I faced the same issue. In fact in Thiruvananthapuram and in Poovar, I could not get Aircel at all. I could not access Internet from any other carrier. When we drove to Kanyakumari from Poovar, the instant we entered Tamil Nadu, my phone connected to the Internet and once we were back into Kerala, it stopped connecting to the Internet.
My Data Roaming is on.
I Reset my Network Settings also.
I'm afraid Aircel Customer Care is not helpful.
Has anyone faced similar issues and managed to resolve it.
Any help will be appreciated.