Data gone

Data disappears like water. No notification and when you try to check on the Vodacom app how much data is left.. the system is not available, not able to log in or a problem has occurred try again later. Once again data all used up and no text message received. But try check your balance via *111# and select balance.. then you receive an sms 'Try our new My vodacom app web version. Check your balances. Click.... not interested..