Lost phone & no other trusted device
My son has lost his iPhone & I’m trying to restore a new phone from his backups. If I attempt to login to his Apple ID it needs a verification code first, by default sent to his lost device. He doesn’t have any other trusted devices (including mine) to send this verification code to, so how do I get hold of this verification code either on my iPhone or turn off the need for it. Have tried various options like logging on to iCloud with his user id to set up my device as trusted but keep hitting the brick wall of needing the verification code first. Just keep going around in circles & is mega frustrating