If you just buy MTN airtime from any vendor, you might be surprised to notice the digits are no longer 12 like they used to be. Fears of it being fake might make you return it back to the vendor. It seems we have exhausted the 12 digit PINs and MTN have migrated to using 16 digits.
They took to their Facebook page to calm any doubts in the minds of users saying :
We wish to confirm that the 16 digit logical PINs currently in circulation are genuine.
While the new 16-digit PINs will ultimately replace the regular 12 digit PIN currently in use, please note that all recharge cards with the 12-digit PIN remain valid while stock last. We urge all customers to purchase their logical PINs and recharge cards from only authorised vendors or retailers
So from henceforth if you come across any MTN Recharge PIN with 16 digits, fear not and use it like you normally do.