Stop messing with pensioner's money, its not right!!

I am having difficulties trying to understand what is going on with my 76 year old mum's debit orders. She has been with Momentum for years. On 1 January they debited R5,197 off her account when the usual amount is R1,743. I contacted the consultant I have been dealing with for years and told him that we had reversed the debit order and for him to please send me bank details and amount to do a manual deposit. He sent the bank details but not the amount. I also sent a copy of the bank statement reflecting the debit order amount which he asked for but have heard nothing since (since we assumed it was a *****ulent debit order due to the amount). Today they debited an amount of R10,394. Momentum are you seriously doing this to a pensioner!! I need someone to please contact me urgently as my emails go unanswered and of course no one picks up at the call centre!!