Data - notifying SMS service

<p>I am very unhappy about the fact that I am nog getting any sms notifications, notifying me that my data has ran out. I used to get a sms each time this happened but this has not been the case for the last couple of months or more. I have run up a huge bill due to data that is being charged at a higher rate which is unacceptable. I do not have a problem buying extra data when it runs out but wants to be notified. Why has this service been discontinued? I have received any notifications that this was going to happen.</p>