Vodacom-what a ******* bunch?!!!

Before I moved to the UAE in July, I migrated my contract to a lower option. I didn't receive any confirmation and had to again contact Vodacom. Poor service delivery! Then I received a statement saying that I had to pay a certain amount for the migration and handset. The amount went off at the beginning of Sep. Now I get a statement for the same amount of my previous contract. When I contact Vodacom I am told that it is for my handset!! And on the statement they charged me for 1G data and minutes as well!!! So they justified it by saying it is for the handset! I was clearly told in July that only the amount for the migration and handset would be deducted once and now I am told no sorry you still have to pay for the handset! It says so clearly on the statement I received in July it is for the HANDSET, but Vodacom is sticking to their story. So they clearly either made a mistake in July for telling me I am paying for the handset once-off or they are trying their luck and deduct another payment for a whole contract fee of R634! This is not the first time I have trouble with Vodacom and I can tell many horror stories. Why do we have to put up with such terrible service delivery?? And why is there always problems when you want to terminate a contract with them??