This is where 90% of users get stuck. When you try to toggle Call Barring off, the phone asks for a password.

If you changed it years ago and forgot, or if the carrier default is different, you will get a "Network Rejected" or "Incorrect Password" error.

Most smartphones allow users to disable call barring through the phone settings. The steps to disable call barring on Android and iOS devices are as follows:

Call barring is typically implemented by the network provider or the phone manufacturer. There are several types of call barring, including:

Some MVNOs (like Mint, Lycamobile) disable USSD barring entirely. In that case, you cannot remove barring via codes – you must use their app or web portal.

If the iPhone settings don't show it, it is likely a carrier setting.