Ask EE. If it is their phone they might be able to unlock, but only if you are the original owner.. But we have had reports that unlocking may have to be done by Apple. Good luck with getting that organised before his birthday. They will only unlock if you are the original owner. May need a visit to an Apple store. THis is not something VM can do. All the Apple phones they sell are unlocked at the start.
Superuser 2017/18 Use Kudos to say thanks Mark answer as "helpful" only when the problem is solved Please don't send me private messages unless I ask you to. I do not work for VM. The advice I give is based on my best understanding of VM policy and practice. You rely on it at your own risk.