False information

After recharging my vodacom account. Vodacom keep sending messages that they have rewarded me with airtime and on a number of occasions they have done it but I never get the airtime. This are the following dates an they promised me free airtime but it was never loaded.: 20/10/2015 R15,00 , 30/09/2015 R27,50, 30/10/2015 R15,00, today's message as well is as follows:Thank you for recharging, Vodacom has given you R6.00 Extra Airtime valid until 15/11/2015 23:59:59. Dial *111# to check your airtime balance.T&Cs apply.