Vodacom takes my money without my consent.

Vodacom staff at Menlyn store are *********** , I took out a contract in January for an iphone x requested that my prepaid number be changed to the contract and on a nano simcard the consultant changed my sim to a nano prepaid and activated the new contract under a different number I went back to the store and the lady gave me an attitude saying that I am giving her alot of work I can leave she will do the switch and change my number to the contract no fees nothing was discussed two days later R276 went of my account I called and was advised it is activation fees why do I have to pay twice because of their stuff up that’s nothing compared to the suprise I got when I called the cantact center my next invoice is for + R24000 I went to the grove Vodacom and this is confirmed that that lady did a huge stuff up and was supposed to cancel this contract a different way in order to retain my number it was also confirmed that she changed my contract without my consent I will get legal advice on this matter as I know my rights as a consumer and if Vodacom attempts to deduct this money I will reverse all until you blacklist me.