This is probably what you are going to get forever, call in and no reply. You can continue to drop them emails or messages everyday (this way you will have black and white records), try to refrain from calling. In case your bank wants proof that you have attempted to contact them privately to resolve the issue, these proofs will come in useful.
Focus your attention and effort in recovering your money through the police and bank. Please lodge a police report 1st before approaching your bank. Good if you can lodge a complaint with Securities Commission Malaysia also. Armed with the police and Securities Commission's report, it will give you more leverage when negotiating with Bank Negara Malaysia to initiate an investigation. Group all the victims (make sure each one lodge their own complaint individually) from the same bank together before approaching the bank personally. Strength in numbers.
Noted your kind advices here. It's frustrating and anger to see those scammers running freely and enjoying. This is like a marathon, not many people can sustain till the end. That's explain why they will not entertain the customers complaint till we fall off.
Anyway we will still continue to chase them. Hopefully we can get more support from related party