MTN Bad service and not receiving data

The worst service I have ever received. Opened a contract beginning October 2018. Promo data promised but till now not received. All the data goes off the day time data although a lot of data is used during the nighttime. Every time I receive a ref number, wait seven days receive an sms stating its been resolved but still the same. I had to scan my contract and email it twice to MTN for them to see what contract I signed. I am paying every month R699 for this unacceptable service. Worst decisions I ever made to move from Vodacom to MTN. Now I am stuck for two years with this contract, and not receiving my monthly promised data. I tried phoning the store where I signed the contract but they only said it is MTN not them, shifting the blame. On the phone weekly for nearly two months to sort this out. Now I am at a stage where I am going to cancel my contract, as I see it, they are in breach of contract by not giving me the paid for data.