Useless service unclear terms and forced signing.

I went into cellucity to add a watch an buds to my contract which I was told would just increase my monthly payment which went all well and I got the devices now I have just been charges 11000rand by vodacom with no explanation, Cellucity have *****ed up the whole contract, and I have had to go back and forth with them just to get the watch working in the first place. I cant survive with 11000 rand debited from my account with no explantion this is not what I signed up for and they don't explain anything properly