How to use Alphanumeric characters to set a iPhone passcode
1. Open setting apps from your main screen.
2. Now tap on ‘Touch ID and Passcode’.
3. You have to enter your current passcode.
4. After that you’ll be in ‘Touch ID and Passcode’ settings.
5. Turn off the simple passcode, enter your current passcode.
6. Now enter your new passcode you can use alphanumeric characters.
7. Tap on Done.