Bad Service of Manager

I am complaining about making an investment of R6.4 million with Tyme bank and they took R32 000 as a fee.....I immediately contacted a manager on the floor and he promised to solve this issue..It is now 3 weeks later and no response. I have written 3 emails and also with no response...Is this how they treat a customer who in invested R6.4 million.....Bad...Bad!!!