Invalid birthday
My brother got an IPhone SE and this is his first one ever, he’s trying to create an Apple ID but when he enters his birthday it says it’s invalid
Contact Apple ID Support for assistance. See the Apple Support articles below for contact information.
Apple ID - Official Apple Support. -
Contact Apple for help with Apple ID account security - Apple Support. * (Link doesn’t always load)
Get Support - Work through the screens to get a chat option. You may have to pick a slightly different problem.
Apple Support schedule phone call. -
From the Apple Support article below.
Without proof of your identity via security questions and other carefully selected criteria, Apple Support can't help you reset a password or perform any other actions on your account. These policies are audited and reviewed on a regular basis.