This password is not your phone’s screen lock PIN, your SIM PIN, or your voicemail password. It is a specific code given to you by your mobile carrier. Where Do You Find the Default Password? Here is the secret that most customer service reps won't tell you: 99% of carriers use the same default password.
We’ve all been there. You pick up your phone to make an urgent call, and instead of a dial tone, you hear a strange, pre-recorded message: “Call Barring is On. Enter Password.” what is call barring password
Think of it as a master lock. If you want to stop your teenager from calling international numbers, you turn call barring on. To do that, the network asks for this password to prove you have permission to change those settings. This password is not your phone’s screen lock