Trading account balance could happens due to :

1. Trading account insufficent fund to hold required margin before Stop Out *

2. Spike/ Gap occur during low margin period **

* Credit bonus recede due to: http://www.ikofx.com/en/index.php/en/trader-area/ikofx-deposit-bonus . 

** Low margin during gap/ spike occur - as order will only triggered after the gap/spike price, this might cause insufficient fund to cope the looses.