Hi Favour, before you can transfer credit for the first time, you have to change the PIN from the default PIN (which is 0000) to a new PIN via SMS or using USSD below:
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Hi Diana, To Reset your PIN- dial *321#; *600#; or *777#, select option 1 for Airtime Share, Select option 3 to Reset PIN, enter your mother's maiden name, enter your Date of...
Hi Ibrahim, you need to contact any of the MTN support channels for them to reset your transfer pin, they will ask you questions on the details you used to register your line...