How to change from 6 digit passcode to 4 digit

Go to Settings/Face ID & Passcode (or Touch ID & Passcode on phones without Face ID), tap Change passcode, enter the 6 digit passcode, then tap Passcode Options and you can select 4 digits. Note that 4 digits is much less secure than 6, so only change it if you have no data on your phone that you don’t mind being stolen.

You should stay with the six number Password. It is much more secure.

Try the following:

1. Open Settings
2. Tap Face ID & Passcode
3. Enter your passcode
4. Tap Change Passcode
5. Enter your passcode
6. Tap Passcode Options
7. Tap 4-Digit Numeric Code
8. Enter your new passcode