My iPad won’t update latest version 13.1
my girlfriend just bought new iphone11
she hasn’t used her account t or an iPhone for years so her number is different now to what it was then . So logging in to many times trying to guess it locked her out.
Apple support said she needs to use another iPhone to download apple support and she can log in and change her number from there. So were doing this on my iPad but I can’t download the app because it won’t download the latest software. It’s up to 12.4.7 and I need 13.1
please help
iPad Air, iOS 12