This will show you how to change PIN code for SIM Card in MIUI 8.
Instructions for other MIUI versions
MIUI 8 introduced a new search bar in settings window. You can use it to find settings a lot faster.
If you use it now, you can skip right to step 4. Simply type in “sim“.
SIM LOCKsection tap on SIM Card name which PIN settings you want to change.
If you haven’t changed your SIM Card name it will simply be name of your mobile provider. In this case it is: Virgin
Lock SIM cardyou can choose if phone should ask for PIN to unlock the SIM Card after each reset and
Change SIM PINoption to change or set new PIN code.