Everyone has that one friend or relative who always needs airtime or data from time to time. If you do not have that type of friend, then you might be the one who needs credit. There are several mobile carriers in Nigeria that let you transfer credit and Glo is one of them.
See How to activate Glo transfer pin?
It is simple. Just enter 132000001234512345# and press the Call/Send button. 00000 is the default password, 12345 is your new password. It has to be typed twice to confirm it.