My phone lists carrier as O2 13.0 does this mean it is locked to o2
Hi I was given a iPhone 4 for Christmas which was sold as unlocked. I see it says Carrier O2 13.0 does this mean it is still locked to O2. I have tried a t mobile sim and all it says is no service. What should I do about this.
Many thanks
iPhone 4, iOS 6.0.1
