Breaking contract

for the last 5 months I have not received my data from the cell phone suppliers, a person phone , I am currently standing in MtN and still , sorry log a call with in 2 weeks someone will contac me! I have done this 4 times and still no data. Payment for my contract I have for them goes o off, I keep my end of the deal , MtN just break contract!! No data for 5 months which end up in me having to buy data. I want to cancel my contract they are breaking our arrangement ! But sorry that is not an option! how is it possible they break contract take money for a contract I signed but do not give me what I am paying for? I am suppose to get 500 my of data per money they are so behind!!!! Then I must hear sorry Mrs Kilian we are striking!!! so they strike break contract I waste my time , money, petrol to try and get results , still nothing!!!! They are taking food out of my kids mouths! I want them to cancel my contact I want to move away from mtn 4 visits to branch a and still nothing is happening! Please can you assist me ! I am a small business owner and without data I am lost they just don't care this was the last visit I will make to mtn they are the worst company in SA!!!