Telkom data ****

I have a contract with Telkom which gives me 40GB per month (20GB anytime and 20GB at night). The data gets loaded on the 1st of each month. So Telkom loaded 40GB on 1 September 2018 and by that evening the 40GB data was finished. And when this happened I was not even connected to the wifi since I was not home so I fail to understand how is this possible. I called Telkom twice and no one could assist until I got hold of a lady who told me that this is confusing because their system shows that the data is still active. She promised me that Telkom will investigate the matter and respond within 48-72 hours during working days . She further explained that they will start counting from Monday (3 September). She provided me with the reference number ********** 7 which I used on Monday when I called them to make a follow up on the matter. Telkom agent told me that the matter would be resolved by Thursday so I should make a follow up by then. I called on Thursday again from the morning with no luck of getting through to them. I called again today and the agent that I spoke to told me that the matter has not been resolved and it will take them 9 days to resolve this. She sounded uninterested as well on the phone. I dont understand what makes this investigation takes so long when it’s them that took my data and now I have to spend extra money for that when I’m paying for data that Telkom takes as and when they want. How is it possible that I can finish data within few hours ( a whole 40GB) with no proper explanation from Telkom and instead I get attitude. And this is not the first time they are doing this because even last month they took about 3.5GB of data with no explanation, they need to tell me if they can’t provide this service to me because I feel ****med by Telkom... How can they take data like that?????? If it means cancelling the contract with them then I am willing to do that because I feel ******!!!!!