Great deals, unexpected mistakes

<p>I have been a mtn user for a very long time. I love their deals and everything about them, unfortunately they have done something witch I can not forgive anymore. My data witch I pay for dissappears after a few minutes of use and before you come to me with all that bulldust about.... Check your downloads, check your usage, check this and check that. Just shut it and listen. I manage my usage. I know when data usage raises. So don't mistake me for a starter noob who never used the Internet. I check my data usage history and I know when something will take a ton of data. Just like I checked it for this month and it didn't show any signs of usage even over 100mb, however, my 2gig is missing without a trace. This exact same thing happened 2 months ago and once it kept happening on my old sim. I loaded 20gb and the 5gb disappeared at the very ending without using it. I loaded 1gig and bam! Disappeared again without even using it. Kept loading and I was forced to get a new sim and forgive mtn for my R600 lost. I find this frustrating and I am scared to be honest that if I go to the shop, they would tell me I used it and "sorry Sir you lost your money". If there is no solution to this I'll stop using R500 +R130 monthly on mtn and move to another service provider. </p>