my data disappeared

i am on a 40gig plus 40gig promotion on the 7/12/2015 i received an e-mail which is my weekly update to say that i have 68 gigs available on the 8/12/2015 i received an e-mail and sms that i have 19gigs available when i called vodacom they said that they are experiencing a problem and they are aware that a lot of people are getting an incorrect balance and they are attending to the problem which will be resolved by the evening.today i again called vodacom to find out my balance which they say is now 8 gigs and again the same story<br> if they have a problem why should we suffer and they can send out a sms to say how little we have left why not sent an sms to say they is a problem