day time bundle used up instead of night owl

Telkom changed the starting time of the night owl data from 11 pm to 12 pm without notifying customers. I only became aware of this change once my daytime data bundle was depleted on the morning of 30/3/15 and I emailed Telkom informing them of the error. Telkom only rep**** that the new hours are from 12:00-7:00 that's why my data is deleted. I think that it is unacceptable because I especially waited till 11:00pm to start my downloads. I especially bought new data bundle and was without data for 2 days and I wanted my 2gb data bundle to last till end April ! I think it's very bad business dealing and UNFAIR!