Non existent network service and customer care

I cannot use any of the 19 gig data bundle I have from Telkom. My device shows that it has and LTE connection but no data usage is coming through. On the Speedtest it also shows that there is no data coming through from Telkom. I have logged numerous faults and was only contacted once when the phone got cut off 10 seconds into our call. I have not been able to speak to any one since and they do not call back. They just bill me every month and give a terrible service as this is not the first time that I cannot use the data I have available.