Using an Australian iPhone 5 in the UK with a UK SIM card
I recently gave my old iPhone 5S to my father in the UK so we could use Facetime to communicate. He has Vodafone account & got his SIM changed to the right size to fit but he cannot activate the phone. I purchased the phone through an Optus contract over 24 months which expired a year ago. Optus claim the phone is NOT network locked & the issue is with the Apple registration of this phone to my account. How can I get this changed or the phone "unlocked" on Apple's servers so my Dad can activate it?