Incorrect Billing

I signed a new contract in August 2015 and i was told by the sales consultant that my membership fee will be R199, and that if i am a member of Sanlam Reality i would get up to 60% discount (which would be based average attendence). however, despite my attendence for the past two months i have been paying R329 and no one knows why, i called planet fitness several times but no one is able to explain the increase, i was never notified about this ridiculous increase, I NEED A PROPER EXPLANATION, this is not what i signed for.