Vodacom upgrade...too difficult for them to do.. Shocking service ce

Have had to call in 4 times to get my upgrade processed, each time being told its cancelled and they can't explain why and each time I was promised to receive a call confirming the upgrade and I will receive a sms, as expected still no confirmation. Also tried to upgrade on line 2 x and no surprise no confirmation either.... How difficult is it to help a customer who wants to extend the contact for another 24 months, what terrible service... Was told to go into a store rather!!! Still no upgrade... Trying since Sunday!