Have posted elsewhere on this within my thread about using a mobile in the USA.
After looking around it appeared that one of the best and cheapest ways to use a phone in the US was to pre-purchase a Three 1-month SIM for £25 int he UK that gives 12 gig of data and unlimited calls etc, for use overseas. My partner has bought 3 of these for family members including me.
We all went on GiffGaff over a year ago - as soon as we purchased the brand new phones (Iphone SEs) so as far as we were concerned they were unlocked. He has put the Three Sim in his own phoen and is up and running with it. When he did the same for mine it said "Sim unsupported'.
I went to the Apple shop and according to their diagnostics my phone is locked into an O2/Tesco network (first I've heard!) and that Giff Gaff uses the O2 network so I need to contact Giff Gaff and get them to send me an unlock code. I've tried to contact GG but can only pose a question on the forum and I've had a lot of replies. The consensus seems to be that I have to buy an O2 PAYG SIM for £15 so that I can then request that they unlock me from their system for a £15 charge. So I am basically joining up to a network I am absolutely sure I am not on in the first place, in order to get them to 'unlock' me. It's nuts and I feel like I am being fleeced plus I am going to have no phone access for 24-72 hours while they do the unlocking.
I am baffled but looks like I am going to have to bite the bullet and cough up another £15. We haven't tried doing my son's phone yet as the trip to New York is a surprise trip and we're holding off telling him until the last minute (and he's plugged into his phone every minute of the day!)
Has anyone come across this before?