Are you using any of this sim and bothered either your sim card was registered completely or was not registered.
Airtel has a code to check if your sim card was registered,for You to know if You airtel sim Card was registered simply dial *764#on the airtel Sim card and dial,and wait for the reply if your sim was registered.If it was not You Will recieve a message to go to any nearest shop to register your Sim Card.
For Mtn, dial *789*1# to know if it was registered completely or not registered ,if it was not registered,go to any nearest shop and register.
746 or 200 is for 9 mobile and for glo You text REG to 746 and send then u Will recieve some messages to confirm your registration
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