I bought a Samsung phone, on the T-Mobile carrier in the US. I went to India last week, and got my unlock code from T-Mobile. My India-Vodafone SIM is working fine, except for the internet. I have called customer care, and have changed all the settings, but it doesn't work.
How can I make internet work?
If the SIM card works, and you can get a network signal, then the deice is unlocked and it is a different error that is stopping internet from working.
It could be due to a number of reasons that internet isn't working, I am going to list them:
Invalid/Wrong APN's
APN (Access Point Names) allow your device to connect to mobile internet. You nust ensure you have the correct ones installed for your network.
Device not compatible with internet system
IIRC, the T-Mobile US network uses a different system... It could be that this system isn't compatible with your Indian network for internet access.
Other than the above, I cannot think of any reason internet wouldn't work when mobile network does. Make sure your network is letting you use the internet (no bars, you have internet with your plan) - otherwise, I do not know.
if your phone is working after inserting the different sim card and working fine your phone is unlocked, and there is no issue in phone unlock, the most likely reason for not working the internet is that your phone APN setting is not configured properly, you must have to configure the correct APN setting for that network,
