Vox is giving me a headache

I returned a router and Vox claimed that I returned a wrong Power supply and charged me R250. I requested to see the wrong power supply and requested to get it back but they have now suspended my wifi even though there is a ticket open to address this issue. How can I pay for something and they keep it ? If its wrong, I must have it back and then I pay them. They ignored that . I'm so saddened about the experience with them the past 2 months. It has been hell and wouldn't recommend them at this stage. Its issue on top of issue. Begging them to activate my wifi after moving, now they have suspended while there's a issue pending to be solved. Costing me money! They claim i have been suspended for "late payment" on the suspension notice but its not that! I work from home and these people cost me a lot since I moved