Oppo
Turn On/Off Call Barring auf Oppo
Call barring on Oppo blocks specific categories of calls at the network level, not just inside the Phone app. That is why a barred call never rings at all: the carrier rejects it before it reaches your SIM.
Coloros groups barring by direction and location: outgoing calls, outgoing international calls, outgoing international roaming calls, incoming calls, and incoming calls while roaming. Each toggle works independently, so switching off one type does not touch the others.
To reach the setting, go to Tap on Phone ➔ Open the Menu ➔ Tap on Settings ➔ Tap on Calling accounts ➔ Tap on Carrier call settings ➔ Tap on Call barring. On dual-SIM devices, pick the correct SIM card first, since barring is set separately for each line.
Inside Call barring, tap the option you want and switch it on or off. Some carriers ask for a barring password the first time you activate a restriction; contact your provider if you never set one up.
If calls stop working entirely after enabling barring, check whether you activated the wrong direction, for example blocking all outgoing calls instead of only outgoing international roaming calls. Turning off the wrong entry restores normal calling right away.