Money being deducted from my account

I lodge a complaint at the branch in Belhar on the 19 August 2017. The complaint reference number is CCM ********** . I phoned the complaints department and explained that over R4800 was deducted from my account since December 2016. The explained to me that someone is purchasing airtime (Vodacom) from my account. I told them that I am Cell C and I don't buy airtime from my account. The lodge the complaint and provided me with the above reference number. Today more money was deducted from account and still I didn't get feedback and money back. I really work hard for my money and I have a family to support. Please advise if I should start looking at banking with a different bank. I really need the money that was deducted from my account.