All Data services with their SHORT CODES to check balance
MTN SME *312*4*3*3#
MTN Data Card *312*5#
MTN GIFTING *312*5#
MTN Corporate Gifting *312*4*7*4# or *312*5#
Airtel CG *140# (check balance under edu bundle)
Airtel GIFTING *140#
GLO GIFTING *127*0#
GLO Corporate Gifting *127*0#
9mobile data *228#
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Data is Life!
May God continue to Bless you #Aameen