VODACOM FRUSTRATION

I am a very unhappy person with Vodacom at the moment. I did my upgrade last month, and only to get an invoice for almost triple the amount this month. No one explained that if you get several sms's to say you are due for an upgrade that your previous device is settled. Now I still have to pay my old device plus new devices for the next 2 months. Do they think money grows on trees in this country. Why do companies not make sure when you go for an upgrade to give you all the facts to make sure you are able to pay the account. This is why 90% of South African people do not have extra money and cannot cope with bills coming the end of the month. Because this is what companies do to you.