Extremely bad MTN service

I've written so many complaints and have visited their stores so many times without my problem being resolved. My father has a 100gbday 100gb night data contract and for 6 months now he is only receiving half of what he should. 50gb and 50gb. The ombudsman or some kind of legal action will have to be taken since hes only getting half and is still paying R1000 which is absurd. To top it all off my signal feom MTN has been almost unusable for the past week, in my family there is 7 MTN contracts that will have to be canceled soon since poor service is all we get. My previous complaint with attached reference numbers for the queries have all been unanswered, please fix my signal, fix your error on the contract and refund him his 600GB!!