Notification that iphone unlocked but sim not valid and itunes not liking sim
I received notification today from T Mobile UK that the iPhone 4S I purchased has now been unlocked.
So I connected the phone, with the T Mobile sim present, to itunes and went through and restored the phone. Once this was done, I then removed the T Mobile Sim and entered my new sim. Turned on the phone and it told me the Sim was not valid. When I plugged it into the PC through iTunes, a message came up that my sim was not a valid sim.
I have tried enabling and disabling my firewall in case it was this.
I have spent hours trying different things, but it still won't accept the new sim, or activate the phone.
Any help appreciated
iPhone 4S, iOS 8.3