I complain but they did nothing until now

I reported my problem with Hellopeter begging of last month but Standard Bank did nothing except to ask for my mother's ID numbers for investigations for more times that I can't even count but they did nothing. They haven't responded to my complain about my mother's investment plan. They didn't even bother to tell me how the procedure works and how far they are with the investigation. The way their service is bad they didn't even give me a call to find out the whole story and tell me where we go from here. As their costumer I want to know what do I do now or how do I approach them now because I reported to Hellopeter and still nothing clearly they don't take their costumers concerns seriously because they did nothing. May you please help me what to do now because the investment is due this month and we can't take less than what we've been promised and what their contract says .