I started off using it with t-mobile, in england, and now here if i try to use it with a different sim it doesnt work. I've been told that it may be a problem with Apple compatibility. How can i work it out?
If you did not purchase it directly from Apple, then you purchased a locked phone. Only the carrier it is locked to can unlock it.
Phones sold at carphone warehouse in the UK are NOT unlocked. They will lock to the first UK carrier used.
Contact your carrier directly (or car phone warehouse if you purchased there) and they may be able to unlock if you explain that you have moved.
carphone warehouse can't do anything about it. Only the carrier it is locked to can unlock it.
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