Troworths price mix up misleading

So last week i bought a skirt at jubilee mall Truworths store which was on sale .The was a red tag price on it n a hand written price on the item . To my suprise without noticing at de store , when i got home and inspected the receipt the skirt was charged at the hand written price istead of the red tagged price which i found misleading for such a big store and again in that case shouldn't the cashier clarify once they notice such mix up. It was more than 100 charged which i ddnt foresee. Can that be rectified.i stil have the skirt n tags n receipt i dont kno if whether to return it amd ask for a refund or il b blamed for not asking right there n them bt i feel its unfair practice .