Brushless dc motor control

I am using a brushless Dc motor 3 phase.. im confused on the six phase and the three phase. I am assuming the other three phases are for when it is high and when the state is low.. such like phase A high and phase A low.. I am using a VI that works with my hall sensors but the motor is twitching forward then twitching backwards.. what could be the reason for this I have attached the code.