Vodacom unauthorized extra charges

I had taken out 3 contract devices at vodacom and as per those contracts I agreed to pay the amount stipulated and agreed upon by both parties on that contract. Then Vodacom decided to activate migrations on the account with my consent or knowledge and the bill went up so these migrations were *****ulent. I queried it with Vodacom and still paid the extra amount. But vodacom completely ignored my concerns and every single month my bill kept going up and my queries underheard. I just kept paying the extra amount and this was an uphill battle every month in store. I logged a final complaint and the in employee in store really did his best to help me but now Head Office is completely ignoring me and they don't care. Stop these migrations! Stop charging me more than my stipulated contract! Stop the *****ulent behavior and the ignorance I am getting !! Fix my problem and treat your customers correctly!!!