Have you ever tried to make a call, only to hear a robotic voice say, “Call Barring is On” or see the dreaded “Connection problem or invalid MMI code” error?
Save that code in your contacts as "Unlock Phone." If you ever run into the "call barring" issue again, just dial it and hit send. call barring turn off
You search online, type in “call barring turn off,” and find a mess of confusing codes ( ##002# , *#31#, etc.) that look like something out of a spy movie. Have you ever tried to make a call,
Don’t worry. You are not alone, and fixing this is easier than you think. type in “call barring turn off