Data bundles disappearing

I have 4 mtn numbers which I use for various items, tablet, ****le and 2 phones. On the tablet I load every month 1 gig and get 1 gig free. The ****le for laptop has been 2 gig and 2 gig free. I had recently loaded data on both ****le and tablet and this is the 2nd month that my data has been disappearing like crazy! I phone mtn to query, speak to a susan, very rude, *********** and deaf and doesn't give a person chance to speak and she doesn't try to understand let alone listen. All she tells me, is im on he internet! I said no ****! Which websites, cos I use 3 specific websites as I am studying online and have been for the past year and I have always come through with 2 gig not even the whole amount for free! Now, the one time lasts me 7days, reload and then 12 days??? Impossible! I ask to speak to a supervisor, she puts me on hold for I dont know how long. I phone back, speak to another consultant, she checks and says the supervisor is busy with someone, she will give him my nr and he will get back to me. Im still waiting!