Even if a broker is banned for some wrong conduct, investors and traders margins are kept in a separate account so those amounts are safe.....so no need to worry....NSE and SEBI wont allow it to vanish in thin air with the investors margin money.....broker cannot withdraw and use up money from that account...it is a fraudulent practice. NSE margining system is so strict that these days it is almost impossible for a broker to default and run away with money even if he wants to.....so be calm ,there is no risk to margin money...
Smart_trade