FNB taking advantage of vulnerable customers

My mother went to submit her proof of residence at FNB Heilbron. They sold gave her the FNB Sim card and told her it is the only way to get hold of their call centre's for assistance. And that if she calls the call centre using her own sim card she will not get assistance. They deduct money from her account every month. When I realized this it was 2 months already deducting and she told me that she was told it is for the call centre. I sent a complaint to FNB complaints and they never even try to respond to me, talk about ******!!! They only sent me a ref number: *** that was the last of it. Stop taking advantage of our elderly vulnerable parents!!!! I wonder how many customers in that branch had fallen victim of this. My mom has not even used the Sim card because she is waiting for a day she needs help from call centre, yet she is paying monthly. Such an ********* thing!!!