Open complaint for 4 months and still under investigation.

I have logged a complaint on 14 July 2018. Today is 14 October 2018 (4 months) and my complaint is still under investigation. i have LTE and every weekend from Friday to Sunday night my speed drops from 30 MB/s to between 3 and 1 MB/s. Monday morning speed is back to normal. Technicians came to investigate and acknowledge that there is a problem. Ever since nothing has been done and I still experience the same issues. Case is still open and not fixed. Every month I'm paying R755 for 100GB and are not treated fairly.