Uncapped (R40) but "fair share policy comes into effect after 150mb is reached"

I am utterly disgusted. Not only have I been a long standing Mtn Customer (just over 10 years) but the amount of money I spend per month (apart from Mtn Contract) amounts to approximately R500 which is used for extra data as Mtn im my opinion is thieving us in broad daylight. With one of the highest Mtn data prices around, I'm honestly re-looking at my options as they are to say the least, sub standard. I purchased an uncapped bundle solely due to the fact that I work from home during the day (which makes use of standard data) and figured that because I needed to use update my applications and download pdfs, I could make use of this without any issue. Alas, my happiness was short-lived as I awoke sometime in the night to find that I'd received an sms saying I've reached the fair share limit of 150mb which to me, I was not even informed of and my download sped would be greatly reduced thereafter. I feel that I've been cheated as I could easily have purchased a way smaller bundle as opposed to this and have now used the very last of my data savings for month hoping that I could have downloaded the much needed pdf but this was not the case as it has only moved 2% in the last 30 minutes. Mtn, you have just lost yet another loyal customer. I absolutely detest your network as I will remain paying my contract but as of today, will no longer be making use of your additional data services I'd previously make. I'm utterly disappointed and to put it quite frankly, ****ed off. It's a total ******* and trust me, soon, your customers will come to realize that you're thieving them just as I have now. In all honesty, please check my records for data purchases and check the times you even billed me unnecessarily when I would have data available yet not enable me to use it, thus making use of my out of bundle airtime to ensure it gets used up quicker. I would appreciate a crediting of my account with immediate effect of the amount I purchased, R40!