OnePlus
Enable or Disable Call Barring auf OnePlus
Call barring on OnePlus phones works through your network operator, not through the OnePlus software itself. It stops outgoing or incoming calls before they are connected, which is useful when you want to avoid roaming charges or restrict certain call types entirely.
You find the setting in the Phone app. Open Open the Phone app ➔ Open the menu ➔ Open the Settings ➔ Tap on Call accounts. On dual SIM devices, choose the SIM you want to configure, since call barring is set separately per SIM card.
Next tap Call barring, then Choose an option from the list your operator supports, such as barring all outgoing calls or all incoming calls. Enter the barring password provided by your operator and confirm with Turn on/off.
If you do not know this password, contact your carrier, since it is not the same as your device PIN. Also note that call barring can conflict with call forwarding rules, so test a call afterward to confirm the setting applied correctly.