You can liquidate your holdings by initiating an outgoing withdrawal (through any of our platforms) and by entering in the current value (or something very close) of your account as the desired withdrawal amount. A liquidation confirmation and acknowledgment screen will appear and once you accept, your positions will be liquidated during the next trade window.
Please note that while your account is liquidating, scheduled transfers will be disabled, as are other deposits / withdrawals into the system. Once your positions have been sold, funds will be transferred back to your linked bank account once the trades settle in 3-5 business days.
If you have additional questions about liquidations, please contact support.